Windows XP Blue Screen of Death STOP Codes
When Windows XP detects a problem from which it cannot recover, it displays Stop messages. These are text-mode error messages that report information about the condition.
Stop messages, sometimes referred to as blue screens (BSoD), contain specific information that can help you diagnose and possibly resolve the problem detected by the Windows kernel.
This list describes these messages and helps you understand and interpret them.
This list is NOT exhaustive or meant to resolve EVERY error.
This list of messages is a guide to individual messages and their possible causes and resolutions... Having a basic understanding of these error messages enables you to communicate with your technical support professional more effectively too.
With all these Stop messages, you can pretty much assume someone else has encountered the problem before you. That is why tying in the error message into www.google.com , posting a notice for help on a relevant newsgroup and entering the stop code into the "Microsoft Knowledge Base" can yield help just when you need it!
Here is the (long) list:
Stop 0x0000000A or IRQL_NOT_LESS_OR_EQUAL
The Stop 0xA message indicates that a kernel-mode process or driver attempted to access a memory location to which it did not have permission, or at a kernel interrupt request level (IRQL) that was too high. A kernel-mode process can access only other processes that have an IRQL lower than, or equal to, its own. This Stop message is typically due to faulty or incompatible hardware or software.
Possible Resolutions:
• A Stop 0xA message might occur after installing a faulty device driver, system service, or firmware. If a Stop message lists a driver by name, disable, remove, or roll back the driver to correct the problem. If disabling or removing drivers resolves the issues, contact the manufacturer about a possible update. Using updated software is especially important for multimedia applications, antivirus scanners, and CD mastering tools.
• A Stop 0xA message might also be due to failing or defective hardware. If a Stop message points to a category of devices (video or disk adapters, for example), try removing or replacing the hardware to determine if it is causing the problem.
• If you encounter a Stop 0xA message while upgrading to Windows XPl, the problem might be due to an incompatible driver, system service, virus scanner, or backup. To avoid problems while upgrading, simplify your hardware configuration and remove all third-party device drivers and system services (including virus scanners) prior to running setup. After you have successfully installed Windows XP, contact the hardware manufacturer to obtain compatible updates.
Stop 0x0000001E or KMODE_EXCEPTION_NOT_HANDLED
The Stop 0x1E message indicates that the Windows XP kernel detected an illegal or unknown processor instruction. The problems that cause Stop 0x1E messages share similarities with those that generate Stop 0xA errors in that they can be due to invalid memory and access violations. This default Windows XP error handler typically intercepts these problems if error-handling routines are not present in the code itself.
Possible Resolutions:
• Stop 0x1E messages typically occur after installing faulty drivers or system services, or they can indicate hardware problems, such as memory and IRQ conflicts. If a Stop message lists a driver by name, disable, remove, or roll it back to correct the problem. If disabling or removing applications and drivers resolves the issue, contact the hardware manufacturer about a possible update. Using updated software is especially important for multimedia applications, antivirus scanners, and CD mastering tools.
• If the Stop message mentions the file Win32k.sys, the source of the error might be a third-party "remote control" program. If such software is installed, you might be able to disable it by starting the system in safe mode. If not, use Recovery Console to manually delete the system service file that is causing the problem.
• Problems can result from system firmware incompatibilities. Many Advanced Configuration and Power Interface (ACPI) issues can be resolved by updating to the latest firmware.
• Other possible causes include insufficient disk space while installing applications or performing certain functions that require more memory. You can free up space by deleting unneeded files. Use Disk Cleanup to increase available disk space. From Recovery Console, remove temporary files (those with .tmp file extensions), Internet cache files, application backup files, and .tmp files generated by Chkdsk.exe or Autochk.exe. You can also choose to install additional applications to another hard disk with more free space or move data files, paging files, and so on.
• The problem might be due to a memory leak caused by an application or service that is not releasing memory correctly. Poolmon (Poolmon.exe) helps you to isolate the components that are causing kernel memory leaks. For more information about troubleshooting memory leaks, see Microsoft Knowledgebase articles Q177415, "How to Use Poolmon to Troubleshoot Kernel Mode Memory Leaks," and Q298102, "Finding Pool Tags Used by Third Party Files Without Using the Debugger."
Stop 0x00000024 or NTFS_FILE_SYSTEM
The Stop 0x24 message indicates that a problem occurred within Ntfs.sys, the driver file that allows the system to read and write to NTFS file system drives. A similar Stop message, 0x23, exists for the file allocation table (FAT16 or FAT32) file systems.
Possible Resolutions:
• Malfunctioning SCSI and Advanced Technology Attachment (ATA) hardware or drivers can also adversely affect the system's ability to read and write to disk, causing errors. If using SCSI hard disks, check for cabling and termination problems between the SCSI controller and the disks. Periodically check Event Viewer for error messages related to SCSI or FASTFAT in the System log or Autochk in the Application log.
• Verify that the tools you use to continually monitor your system, such as virus scanners, backup programs, or disk defragmenters are compatible with Windows XP. Some disks and adapters come packaged with diagnostic software that you can use to run hardware tests.
To test hard disk or volume integrity
Method 1:
1. In the Run dialog box, in the Open box type:
cmd
2. Start the Chkdsk tool, which detects and attempts to resolve file system structural corruption. At the command prompt type:
chkdsk drive: /f
Method 2:
1. Double-click My Computer, and then select the hard disk you want to check.
2. On the File menu, click Properties.
3. Click the Tools tab.
4. In the Error-checking box, click Check Now.
5. In Check disk options, select the Scan for and attempt recovery of bad sectors check box. You can also select the Automatically fix file system errors check box.
If the volume you are checking is in use, a message asks whether you want to delay disk error checking until the next time you restart your computer. After you restart, disk error checking runs and the volume chosen is not available to run other tasks during this process. If you cannot restart the computer due to the error, use safe mode or Recovery Console.
If you are not using the NTFS file system, and the system partition is formatted with the file allocation table (FAT16 or FAT32) file system, long file name (LFN) information can be lost if hard disk tools are started from an MS-DOS command prompt. A command prompt appears when using a startup floppy disk or when using the command prompt startup option on multiple boot systems that use FAT16 or FAT32 partitions with Microsoft® Windows® 95 OEM Service Release 2 (OSR2), Microsoft® Windows® 98, or Microsoft® Windows® Millennium Edition (Me) installed. Do not use tools meant for other operating systems on Windows XP partitions!
• Nonpaged pool memory might be depleted, which can cause the system to stop. You can resolve this situation by adding more RAM, which increases the quantity of nonpaged pool memory available to the kernel.
Stop 0x0000002E or DATA_BUS_ERROR
The Stop 0x2E message indicates a system memory parity error. The cause is typically failed or defective RAM (including motherboard, Level 2 cache, or video memory), incompatible or mismatched memory hardware, or when a device driver attempts to access an address in the 0x8xxxxxxx range that does not exist (does not map to a physical address). A Stop 0x2E message can also indicate hard disk damage caused by viruses or other problems.
Possible Resolutions:
• Stop 0x2E is typically due to defective, malfunctioning, or failed memory hardware, such as memory modules, Level 2 (L2) SRAM cache, or video adapter RAM. If you added new hardware recently, remove and replace it to determine if it is causing or contributing to the problem. Run diagnostics software supplied by the system manufacturer to determine if the component has failed.
• Stop 0x2E messages can also occur after installing faulty drivers or system services. If a file name is given, you need to disable, remove, or roll back that driver. Disable the service or application and confirm that this resolves the error. If so, contact the hardware manufacturer about a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, and CD mastering tools.
• Hard disk corruption can also cause this Stop message.
• The problem might also be due to cracks, scratched traces, or defective components on the motherboard. If all else fails, take the system motherboard to a repair facility for diagnostic testing.
Stop 0x0000003F or NO_MORE_SYSTEM_PTES
The Stop 0x3F message indicates one or more of the following problems:
• The system Page Table Entries (PTEs) are depleted or fragmented due to the system performing a large number of input/output (I/O) actions.
• A faulty device driver is not managing memory properly.
• An application, such as a backup program, is improperly allocating large amounts of kernel memory.
Possible Resolutions:
• Stop 0x3F messages can occur after installing faulty drivers or system services. If a file name is given, you need to disable, remove, or roll back that driver. Disable the service or application and confirm that this resolves the error. If so, contact the hardware manufacturer about a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, and CD mastering tools.
• The system might not actually be out of PTEs, but a contiguous memory block of sufficient size is not available to satisfy a driver or application request. Check for the availability of updated driver or application files and consult the hardware or program documentation for minimum system requirements.
• Another cause is excessive demands for system PTE by applications. This situation is more common in server environments. Windows XP Professional provides a registry entry, SystemPages, that you can use to increase the number of PTEs allocated.
Caution
o Do not edit the registry unless you have no alternative. The registry editor bypasses standard safeguards, allowing settings that can damage your system, or even require you to reinstall Windows. If you must edit the registry, back it up first...
To increase the number of PTEs allocated in the registry
1. In the Run dialog box, and in the Open box, type: regedit
2. In the registry editor, navigate to the subkey HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\
Session Manager\Memory Management.
3. Double-click on PagedPoolSize and SystemPages to view the value for each entry.
4. If PagedPoolSize is not zero, assign a value of 0.
5. If SystemPages is not zero, assign a value of 40000 for systems with 128 MB (or less) of memory, or 110000 for systems with 128 MB to 256 MB of memory. For systems with more memory, do not increase the SystemPages value above 110000 without contacting Microsoft technical support.
6. Click OK, and then close the registry editor.
7. Restart your computer.
Stop 0x00000050 or PAGE_FAULT_IN_NONPAGED_AREA
The Stop 0x50 message indicates that requested data was not in memory. The system generates an exception error when using a reference to an invalid system memory address. Defective memory (including main memory, L2 RAM cache, video RAM) or incompatible software (including remote control and antivirus software) might cause Stop 0x50 messages.
Possible Resolutions:
• If you added new hardware recently, remove and replace the hardware to determine if it is causing or contributing to the problem. Run diagnostics software supplied by the hardware manufacturer to determine if the component has failed.
• Stop 0x50 messages can also occur after installing faulty drivers or system services. If the file name is listed, you need to disable, remove, or roll back that driver. If not, disable the recently installed service or application to determine if this resolves the error. If this does not resolve the problem, contact the hardware manufacturer for updates. Using updated drivers and software is especially important for network interface cards, video adapters, backup programs, multimedia applications, antivirus scanners, and CD mastering tools. If an updated driver is not available, attempt to use a driver from a similar device in the same family. For example, if printing to a Model 1100C printer causes Stop 0x50 errors, using a printer driver meant for a Model 1100A or Model 1000 might temporarily resolve the problem.
Stop 0x00000077 or KERNEL_STACK_INPAGE_ERROR
The Stop 0x77 message indicates that a page of kernel data requested from the paging (virtual memory) file could not be found or read into memory. This Stop message can also indicate disk hardware failure, disk data corruption, or possible virus infection.
Possible Resolutions:
• Stop 0x77 messages can be caused by bad sectors in the virtual memory paging file or a disk controller error. In extremely rare cases, depleted nonpaged pool resources can cause this error. If the first and third parameters are zero, the stack signature in the kernel stack is missing, which is an error typically caused by defective hardware. If the I/O status is 0xC0000185 and the paging file is on a SCSI disk, check for cabling and termination issues. An I/O status code of 0xC000009C or 0xC000016A indicates that the requested data could not be found. You can try to correct this by restarting the computer. If a problem with disk integrity exists, Autochk, a program that attempts to mark bad disk sectors as defective so that they are not used in the future, starts automatically. If Autochk fails to run, you can manually perform the integrity check yourself by following the instructions to run Chkdsk provided in "Stop 0x00000024 or NTFS_FILE_SYSTEM" earlier in this list.
• Another cause of Stop 0x77 messages is defective, malfunctioning, or failed memory hardware, such as memory modules, Level 2 (L2) SRAM cache, or video adapter RAM. If you added new hardware recently, remove and replace it to determine if it is causing or contributing to the problem. Run diagnostics software supplied by the system manufacturer to determine if the component has failed.
• The problem might also be due to cracks, scratched traces, or defective components on the motherboard. If all else fails, take the system motherboard to a repair facility for diagnostic testing.
• Problems that cause Stop 0x77 messages can also cause Stop 0x7A messages. For more information about Stop 0x7A messages, see "Stop 0x0000007A or KERNEL_DATA_INPAGE_ERROR" later in this list.
Stop 0x00000079 or MISMATCHED_HAL
The Stop 0x79 message indicates that the hardware abstraction layer (HAL) and the kernel type for the computer do not match. This error most often occurs when ACPI firmware settings are changed. For example, you might install Windows XP on an x86-based computer with the firmware ACPI enable option enabled and later decide to disable it. This error can also result when mismatched single and multi-processor configuration files are copied to the system.
Possible Resolutions:
• A Stop 0x79 message occurs when the system is using out-of-date Ntoskrnl.exe or Hal.dll files. This can occur after manual repairs that involve copying incorrect files to the system. This error also occurs when using mismatched files, such as copying a multiprocessor HAL on to a system using a single-processor kernel (or vice versa). The kernel and HAL files for single-processor and multiprocessor systems are stored on the Windows XP Professional operating system CD using two different file names. For example, the single and multi-processor versions of the kernel, named Ntoskrnl.exe and Ntkrnlmp.exe respectively. Setup copies either Ntoskrnl.exe or Ntkrnlmp.exe to your system as Ntoskrnl.exe. In Recovery Console, you can use the Copy command to copy the correct HAL or kernel files from the CD to the appropriate folder on the hard disk.
• If you experience Stop 0x79 messages after changing firmware settings, restore the original settings used during Windows XP Professional Setup.
Because systems that use the ACPI HAL ignore IRQ assignments stored in firmware, you can only manually change IRQ settings for non-ACPI (Standard PC HAL) systems. Some x86-based provide the option to toggle ACPI functionality. To disable or re-enable ACPI, you must change firmware settings and reinstall Windows XP. Because of the numerous registry and system file changes required, you must run Setup again (an upgrade installation does not work).
Stop 0x0000007A or KERNEL_DATA_INPAGE_ERROR
The Stop 0x7A message indicates that a page of kernel data was not found in the paging (virtual memory) file and could not be read into memory. This might be due to incompatible disk or controller drivers, firmware, or hardware.
Frequently, the cause of this error can be determined from the second parameter, the I/O status code. Some common status codes are:
• 0xC000009A, or STATUS_INSUFFICIENT_RESOURCES, indicates a lack of nonpaged pool resources.
• 0xC000009C, or STATUS_DEVICE_DATA_ERROR, indicates bad blocks (sectors) on the hard disk.
• 0xC000009D, or STATUS_DEVICE_NOT_CONNECTED, indicates defective or loose data or power cables, a problem with SCSI termination, or improper controller or disk configuration.
• 0xC000016A, or STATUS_DISK_OPERATION_FAILED, indicates bad blocks (sectors) on the hard disk.
• 0xC0000185, or STATUS_IO_DEVICE_ERROR, indicates improper termination, defective storage controller hardware, or defective disk cabling, or two devices attempting to use the same resources.
Possible Resolutions:
• Stop 0x7A can be caused by bad sectors in the virtual memory paging file, disk controller error, virus infection, or memory hardware problems. In extremely rare cases, depleted nonpaged pool resources can cause this error. If the first and third parameters are zero, the stack signature in the kernel stack is missing, an error typically caused by defective hardware. If the I/O status is 0xC0000185 and the paging file is on a SCSI disk, check for cabling and termination issues. An I/O status code of 0xC000009C or 0xC000016A indicates that the requested data could not be found. You can try to correct this by restarting the computer. If a problem with disk integrity exists, Autochk, a program that attempts to mark bad disk sectors as defective so that they are not used in the future, starts automatically. If Autochk fails to run, you can manually perform the integrity check yourself by following the instructions to run Chkdsk provided in "Stop 0x00000024 or NTFS_FILE_SYSTEM" earlier in this appendix.
• Another cause of Stop 0x7A messages is defective, malfunctioning, or failed memory hardware, such as memory modules, Level 2 (L2) SRAM cache, or video adapter RAM. If you added new hardware recently, remove and replace it to determine if it is causing or contributing to the problem. Run diagnostics software supplied by the system manufacturer to determine if the component has failed.
• Check the hardware manufacturer's Web site for updates to disk adapter firmware or drivers that improve compatibility. Verify that your disks and controller support the same set of advanced features, such as higher transfer rates. If necessary, select a slower transfer rate if an update is not yet available. Consult your hardware or device documentation for more information.
IMPORTANT
o You can install disk controller drivers not present on the Windows XP Professional operating system CD by responding to the following prompt shortly after starting Setup:
o Press F6 if you need to install a third party SCSI or RAID driver.
o Press F6, and when prompted, provide the appropriate storage controller driver (ATA or SCSI) supplied by the manufacturer.
• The problem might also be due to cracks, scratched traces, or defective components on the motherboard. If all else fails, take the system motherboard to a repair facility for diagnostic testing.
• Problems that cause Stop 0x7A messages can also cause Stop 0x77 messages. For more information about Stop 0x77 messages, see "Stop 0x00000077 or KERNEL_STACK_INPAGE_ERROR" earlier in this list.
Stop 0x0000007B or INACCESSIBLE_BOOT_DEVICE
The Stop 0x7B message indicates that Windows XP has lost access to the system partition or boot volume during the startup process. Installing incorrect device drivers when installing or upgrading storage adapter hardware typically causes stop 0x7B errors. Stop 0x7B errors could also indicate possible virus infection.
The second parameter is very important because it can indicate whether the 0x7B Stop message was caused by file system issues or problems with storage hardware and drivers. Values of 0xC000034 or 0xC000000E typically indicate:
• Disks or storage controllers that are failing, defective, or improperly configured.
• Storage-related drivers or programs (tape management software, for example) that are not fully compatible with Windows XP Professional.
Possible Resolutions:
• During I/O system initialization, the controller or driver for the startup device (typically the hard disk) might have failed to initialize the necessary hardware. File system initialization might have failed because of disk or controller failure, or because the file system did not recognize the data on the boot device.
• Repartitioning disks, adding new disks, or upgrading to a new disk controller might cause the information in the Boot.ini file, or Boot Manager, to become outdated. If this Stop message occurs after installing new disks to your system, edit the Boot.ini file or adjust the Boot Manager parameters to allow the system to start. If the error occurs after upgrading the disk controller, verify that the new hardware is functioning and correctly configured.
• Verify that the system firmware and disk controller BIOS settings are correct and that the storage device was properly installed. If you are unsure, consult your computer's documentation about restoring default firmware settings or configuring your system to auto-detect settings. If the error occurs during Windows XP Professional setup, the problem might be due to unsupported disk controller hardware. In some cases, drivers for new hardware are not in the Windows XP Professional Driver.cab library, and you need to provide additional drivers to complete the Windows XP setup successfully. If this is the case, follow the hardware manufacturer's instructions when installing drivers. Periodically check for driver and firmware updates.
• Hard disk corruption can also cause this Stop message. For more information about checking hard disk integrity, see the instructions provided in "Stop 0x00000024 or NTFS_FILE_SYSTEM" earlier in this list.
• Problems that cause 0x7B errors might also cause Stop 0xED errors. For more information about 0xED Stop messages, see "Stop 0x0000007B or INACCESSIBLE_BOOT_DEVICE" later in this list.
Stop 0x0000007F or UNEXPECTED_KERNEL_MODE_TRAP
The Stop 0x7F message indicates that one of three types of problems occurred in kernel-mode:
• A condition that the kernel is not allowed to have or intercept (also known as a bound trap).
• Software problems.
• Hardware failures.
Possible Resolutions:
• Stop 0x7F messages are typically due to defective, malfunctioning, or failed memory hardware. If you added new hardware recently, remove and replace it to determine if it is causing or contributing to the problem. Run diagnostics software supplied by the system manufacturer to determine if the component has failed.
• Running the CPU beyond the rated specification, known as "overclocking," can cause Stop 0x7F or other error messages due to heat buildup. When diagnosing problems on overclocked systems, first restore all clock and bus speed settings to the manufacturer recommended values to determine if this resolves the issues.
• The problem might also be due to cracks, scratched traces, or defective components on the motherboard. If all else fails, take the system motherboard to a repair facility for diagnostic testing.
• Stop 0x7F messages can occur after installing incompatible applications, drivers, or system services. Contact the software manufacturer about possible Windows XP specific updates. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, and CD mastering tools.
Stop 0x0000009F or DRIVER_POWER_STATE_FAILURE
The Stop 0x9F message indicates that a driver is in an inconsistent or invalid power state.
Possible Resolutions:
• Stop 0x9F messages can occur after installing faulty applications or drivers or system services. If a file is listed by name and you can associate it with an application, uninstall the application. For drivers, disable, remove, or roll back that driver to to determine if this resolves the error. If it does, contact the hardware manufacturer for a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, and CD mastering tools.
• For information about troubleshooting standby and hibernate mode issues, see KB article Q266169, "How to Troubleshoot Problems with Standby Mode, Hibernate Mode, and Shutting Down Your Computer in Windows 2000."
Stop 0xBE or ATTEMPTED_WRITE_TO_READONLY_MEMORY
The Stop 0xBE message indicates that a driver attempted to write to read-only memory.
Possible Resolutions:
• A Stop 0xBE message might occur after installing a faulty device driver, system service, or firmware. If a Stop message lists a driver by name, disable, remove, or roll back the driver to correct the problem. If disabling or removing drivers resolves the issues, contact the manufacturer about a possible update. Using updated software is especially important for multimedia applications, antivirus scanners, DVD playback, and CD mastering tools.
Stop 0xC2 or BAD_POOL_CALLER
The Stop 0xC2 message indicates that a kernel-mode process or driver incorrectly attempted to perform memory operations in the following ways:
• By allocating a memory pool size of zero bytes.
• By allocating a memory pool that does not exist.
• By attempting to free a memory pool that is already free.
• By allocating or freeing a memory pool at an IRQL that was too high.
This Stop message is typically due to a faulty driver or software.
Possible Resolutions:
• A Stop 0xC2 messages might occur after installing a faulty device driver, system service, or firmware. If a Stop message lists a driver by name, disable, remove, or roll back the driver to correct the problem. If disabling or removing drivers resolves the issues, contact the manufacturer about a possible update. Using updated software is especially important for multimedia applications, antivirus scanners, DVD playback, and CD mastering tools.
• A Stop 0xC2 messages might also be due to failing or defective hardware. If a Stop message points to a category of devices (such as disk controllers, for example), try removing or replacing the hardware to determine if it is causing the problem.
• If you encounter a Stop 0xC2 message while upgrading to Windows XP, the problem might be due to an incompatible driver, system service, virus scanner, or backup. To avoid problems while upgrading, simplify your hardware configuration and remove all third-party device drivers and system services (including virus scanners) prior to running setup. After you have successfully installed Windows XP, contact the hardware manufacturer to obtain compatible updates.
Stop 0x000000CE or DRIVER_UNLOADED_WITHOUT
_CANCELLING_PENDING_OPERATIONS
This Stop messages indicates that a driver failed to cancel pending operations before exiting.
Possible Resolutions:
• Stop 0xCE messages can occur after installing faulty drivers or system services. If a driver is listed by name, disable, remove, or roll back that driver to confirm that this resolves the error. If so, contact the manufacturer about a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, DVD playback, and CD mastering tools.
Stop 0x000000D1 or DRIVER_IRQL_NOT_LESS_OR_EQUAL
The Stop 0xD1 messages indicates that the system attempted to access pageable memory using a kernel process IRQL that was too high. Drivers that have used improper addresses typically cause this error.
Possible Resolutions:
• Stop 0xD1 messages can occur after installing faulty drivers or system services. If a driver is listed by name, disable, remove, or roll back that driver to confirm that this resolves the error. If so, contact the manufacturer about a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, DVD playback, and CD mastering tools.
Stop 0x000000EA or THREAD_STUCK_IN_DEVICE_DRIVER
A device driver problem is causing the system to pause indefinitely. Typically, this problem is caused by a display driver waiting for the video hardware to enter an idle state. This might indicate a hardware problem with the video adapter or a faulty video driver.
Possible Resolutions:
• Stop 0xD1 messages can occur after installing faulty drivers (especially video drivers) or system services. If a driver is listed by name, disable, remove, or roll back that driver to confirm that this resolves the error. If so, contact the manufacturer about a possible update. Using updated software is especially important for backup programs, multimedia applications, antivirus scanners, DVD playback, and CD mastering tools.
Stop 0x000000ED or UNMOUNTABLE_BOOT_VOLUME
The kernel mode I/O subsystem attempted to mount the boot volume and it failed. This error might also occur during an upgrade to Windows XP Professional on systems that use higher throughput ATA disks or controllers with incorrect cabling. In some cases, your system might appear to work normally after you restart.
Possible Resolutions:
• If using higher throughput ATA disks and controllers, those capable of data transfer rates above 33.3 megabytes per second, replace the standard 40-pin cable with an 80-pin cable. Using an 80-pin cable is optional for transfer rates up to and including 33.3 megabytes per second, but is mandatory for higher transfer rates. The additional grounded pins are required to avoid data loss.
• Some firmware enables you to force higher transfer rates even when you are using the incorrect cable type. Your firmware might issue a warning but allow the startup process to proceed. Restore the default firmware setting for ATA cable detection.
• Problems that cause 0xED errors might also cause Stop 0x7B errors. For more information about 0x7B Stop messages, see "Stop 0x0000007B or INACCESSIBLE_BOOT_DEVICE" earlier in this appendix.
Stop 0xC0000221 or STATUS_IMAGE_CHECKSUM_MISMATCH
This Stop message indicates driver, system file, or disk corruption problems (such as a damaged paging file). Faulty memory hardware can also cause this Stop message to appear.
Possible Resolutions:
• You can use Driver Rollback or System Restore from safe mode, to restore a previous driver. You can also use Windows XP Professional recovery features such as the Last Known Good Configuration startup option, Backup, or Automated System Recovery to restore a previous working configuration. After restoring from backup media, you might need to reapply service packs or hotfixes, depending on when the backups were made.
• If the Stop message names the specific file, try replacing it manually with a fresh copy from the Windows XP Professional operating system CD using safe mode or Recovery Console. For systems using the FAT16 or FAT32 file system, you have the option of using a Windows 98 or Windows Millennium Edition Emergency Boot Disk to access the hard disk.
If the original file from the operating system CD has a file name that ends with an underscore (_) character, you cannot use the file until it is uncompressed. The Recovery Console's Copy command is ideal for copying compressed files because it detects and expands them. If you do not specify a destination file name, you must rename the expanded file with the correct extension before using it. From safe mode or Recovery Console, you can use the Expand command to uncompress and copy a file to a destination location. In Recovery Console, the expanded file is given the correct name after being copied to the destination location. For more information about the Copy or Expand commands, see Windows XP Help and Support Centre.
MP3 Rocket 5.3.5
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Rapidshare tricks
Here i wuld tell u an easier way to download rapidshare files without any time and size limits of the files.
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click on that link to dowload ur file and u can see that the downloading speed is much more than a normal speed.
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Ettercap NG-0.7.3 RELEASED
Guys Ettercap is one of the popular tools for MITM(Man in the middle attack).
So its nothing but u can act as a middle man between any two victims who are chatting online in a LAN network and see their conversations and send them messages in the way that both victims are communicating with each other.BUT u remain invisble or unknown to them as they think u to be the real man chatting.
Ettercap is a suite for man in the middle attacks on LAN. It features sniffing of live connections, content filtering on the fly and many other interesting tricks.
It supports active and passive dissection of many protocols (even ciphered ones) and includes many feature for network and host analysis.
For download of this tool visit the site.
ettercap.sourceforge.net
So its nothing but u can act as a middle man between any two victims who are chatting online in a LAN network and see their conversations and send them messages in the way that both victims are communicating with each other.BUT u remain invisble or unknown to them as they think u to be the real man chatting.
Ettercap is a suite for man in the middle attacks on LAN. It features sniffing of live connections, content filtering on the fly and many other interesting tricks.
It supports active and passive dissection of many protocols (even ciphered ones) and includes many feature for network and host analysis.
For download of this tool visit the site.
ettercap.sourceforge.net
Hackers Dictionary
Here is the word document which gives all the details of Internet,Computer,Networking related words....
Download here:
Hackers A-Z
Download here:
Hackers A-Z
Cain & Abel v4.9.35 – Password Sniffer, Cracker and Brute-Forcing Tool
It’s been quite a while since we’ve written about Cain & Abel, one of the most powerful tools for the Windows platform (back in 2007 here).
Cain & Abel is a password recovery tool for Microsoft Operating Systems. It allows easy recovery of various kind of passwords by sniffing the network, cracking encrypted passwords using Dictionary, Brute-Force and Cryptanalysis attacks, recording VoIP conversations, decoding scrambled passwords, recovering wireless network keys, revealing password boxes, uncovering cached passwords and analyzing routing protocols. The program does not exploit any software vulnerabilities or bugs that could not be fixed with little effort. It covers some security aspects/weakness present in protocol’s standards, authentication methods and caching mechanisms; its main purpose is the simplified recovery of passwords and credentials from various sources, however it also ships some “non standard” utilities for Microsoft Windows users.
Cain & Abel has been developed in the hope that it will be useful for network administrators, teachers, security consultants/professionals, forensic staff, security software vendors, professional penetration tester and everyone else that plans to use it for ethical reasons. The author will not help or support any illegal activity done with this program. Be warned that there is the possibility that you will cause damages and/or loss of data using this software and that in no events shall the author be liable for such damages or loss of data. Please carefully read the License Agreement included in the program before using it.
The latest version is faster and contains a lot of new features like APR (Arp Poison Routing) which enables sniffing on switched LANs and Man-in-the-Middle attacks. The sniffer in this version can also analyze encrypted protocols such as SSH-1 and HTTPS, and contains filters to capture credentials from a wide range of authentication mechanisms. The new version also ships routing protocols authentication monitors and routes extractors, dictionary and brute-force crackers for all common hashing algorithms and for several specific authentications, password/hash calculators, cryptanalysis attacks, password decoders and some not so common utilities related to network and system security.
Most recently added is the support for Windows 2008 Terminal Server in APR-RDP sniffer filter.
You can download Cain & Abel v4.9.35 here:
ca_setup.exe
Cain & Abel is a password recovery tool for Microsoft Operating Systems. It allows easy recovery of various kind of passwords by sniffing the network, cracking encrypted passwords using Dictionary, Brute-Force and Cryptanalysis attacks, recording VoIP conversations, decoding scrambled passwords, recovering wireless network keys, revealing password boxes, uncovering cached passwords and analyzing routing protocols. The program does not exploit any software vulnerabilities or bugs that could not be fixed with little effort. It covers some security aspects/weakness present in protocol’s standards, authentication methods and caching mechanisms; its main purpose is the simplified recovery of passwords and credentials from various sources, however it also ships some “non standard” utilities for Microsoft Windows users.
Cain & Abel has been developed in the hope that it will be useful for network administrators, teachers, security consultants/professionals, forensic staff, security software vendors, professional penetration tester and everyone else that plans to use it for ethical reasons. The author will not help or support any illegal activity done with this program. Be warned that there is the possibility that you will cause damages and/or loss of data using this software and that in no events shall the author be liable for such damages or loss of data. Please carefully read the License Agreement included in the program before using it.
The latest version is faster and contains a lot of new features like APR (Arp Poison Routing) which enables sniffing on switched LANs and Man-in-the-Middle attacks. The sniffer in this version can also analyze encrypted protocols such as SSH-1 and HTTPS, and contains filters to capture credentials from a wide range of authentication mechanisms. The new version also ships routing protocols authentication monitors and routes extractors, dictionary and brute-force crackers for all common hashing algorithms and for several specific authentications, password/hash calculators, cryptanalysis attacks, password decoders and some not so common utilities related to network and system security.
Most recently added is the support for Windows 2008 Terminal Server in APR-RDP sniffer filter.
You can download Cain & Abel v4.9.35 here:
ca_setup.exe
Katana v1 (Kyuzo) – Portable Multi-Boot Security Suite
The Katana: Portable Multi-Boot Security Suite is designed to fulfill many of your computer security needs. The idea behind this tool is to bring together many of the best security distributions and applications to run from one USB Flash Drive. Instead of keeping track of dozens of CDs and DVDs loaded with your favorite security tools, you can keep them all conveniently in your pocket.
Katana includes distributions which focus on Penetration Testing, Auditing, Password Cracking, Forensics and Honey Pots. Katana comes with over 100 portable Windows applications, such as Wireshark, HiJackThis, Unstoppable Copier, Firefox, and OllyDBG. It also includes the following distributions:
* Backtrack 4 pre
* the Ultimate Boot CD
* Ophcrack Live
* Damn Small Linux
* the Ultimate Boot CD for Windows
* Got Root? Slax
* Organizational Systems Wireless Auditor (OSWA) Assistant
* Damn Vulnerable Linux
Katana is also highly customizable. You can modify Katana by adding or removing distributions and portable apps with ease. You can add functionality to distributions like the Ultimate Boot CD, Got Root? Slax and UBCD4Win. You can also load your personal scripts and documents to keep them conveniently with
you on your flash drive to use in concert with the provided tools.
You can download Katana v1 here:
http://gextrade.thegoodhacker.com/katana/katana-v1.rar
Katana
Katana includes distributions which focus on Penetration Testing, Auditing, Password Cracking, Forensics and Honey Pots. Katana comes with over 100 portable Windows applications, such as Wireshark, HiJackThis, Unstoppable Copier, Firefox, and OllyDBG. It also includes the following distributions:
* Backtrack 4 pre
* the Ultimate Boot CD
* Ophcrack Live
* Damn Small Linux
* the Ultimate Boot CD for Windows
* Got Root? Slax
* Organizational Systems Wireless Auditor (OSWA) Assistant
* Damn Vulnerable Linux
Katana is also highly customizable. You can modify Katana by adding or removing distributions and portable apps with ease. You can add functionality to distributions like the Ultimate Boot CD, Got Root? Slax and UBCD4Win. You can also load your personal scripts and documents to keep them conveniently with
you on your flash drive to use in concert with the provided tools.
You can download Katana v1 here:
http://gextrade.thegoodhacker.com/katana/katana-v1.rar
Katana
Java program on FLAMES
import java.io.*;
class string2
{
public static void main(String args[]) throws IOException
{ int m;
BufferedReader br=new BufferedReader(new
InputStreamReader(System.in));
System.out.println("Enter ur name: ");
String first=br.readLine();
System.out.println("Enter ur partner's name: ");
String second=br.readLine();
StringBuffer s1=new StringBuffer(first);
StringBuffer s2=new StringBuffer(second);
int a=s1.length();
int b=s2.length();
//comparing two names
label: for(int i=0;i< a;i++)
{
char c=s1.charAt(i);
// System.out.println(c);
for(int j=0;j< b;j++)
{
char d=s2.charAt(j);
if(c==d)
{
////k++;
s1.deleteCharAt(i);
s2.deleteCharAt(j);
////System.out.println(s1 +" " +s2);
a=s1.length();
//m=a;
b=s2.length();
i=0;
j=0;
// continue label;
}
}
//// System.out.println(k);
}
int d=(a+b);
System.out.println("the number is : " +d);
//int n=-1,l=0,p=0;
StringBuffer s3=new StringBuffer("flames");
String s4=new String();
label1: for(int i=0;i< 5;i++)
{int n=-1,l=0,p=0;
for(int j=1;j< =d;j++)
{
n++;
l++;
//int p=0;
if(n>s3.length()-1)
{
char e=s3.charAt(p);
if(l==d)
{
s3.deleteCharAt(p);
//String s4=new String();
s4=s3.substring(p,s3.length());
////System.out.println(s4);
s3.delete(p,s3.length());
////System.out.println(s3);
s3.insert(0,s4);
////System.out.println(s3);
break;
}
else{ p++;
if(p==s3.length())
{p=0;
}
}
}
else
{
char e=s3.charAt(n);
if(l==d)
{
s3.deleteCharAt(n);
s4=s3.substring(n,s3.length());
////System.out.println(s4);
s3.delete(n,s3.length());
////System.out.println(s3);
s3.insert(0,s4);
////System.out.println(s3);
break;
}
//break;
}
}
}
////System.out.println(s3);
char result=s3.charAt(0);
switch(result){
case 'f':
System.out.println(second+" is ur Friend");
break;
case 'l':
System.out.println(second+" is ur Love");
break;
case 'a':
System.out.println(second+" is ur Affection");
break;
case 'm':
System.out.println("u r going to marry "+ second);
break;
case 'e':
System.out.println(second + " is ur Enemy");
break;
case 's':
System.out.println(second +" is ur Sister");
break;
}
}
}
class string2
{
public static void main(String args[]) throws IOException
{ int m;
BufferedReader br=new BufferedReader(new
InputStreamReader(System.in));
System.out.println("Enter ur name: ");
String first=br.readLine();
System.out.println("Enter ur partner's name: ");
String second=br.readLine();
StringBuffer s1=new StringBuffer(first);
StringBuffer s2=new StringBuffer(second);
int a=s1.length();
int b=s2.length();
//comparing two names
label: for(int i=0;i< a;i++)
{
char c=s1.charAt(i);
// System.out.println(c);
for(int j=0;j< b;j++)
{
char d=s2.charAt(j);
if(c==d)
{
////k++;
s1.deleteCharAt(i);
s2.deleteCharAt(j);
////System.out.println(s1 +" " +s2);
a=s1.length();
//m=a;
b=s2.length();
i=0;
j=0;
// continue label;
}
}
//// System.out.println(k);
}
int d=(a+b);
System.out.println("the number is : " +d);
//int n=-1,l=0,p=0;
StringBuffer s3=new StringBuffer("flames");
String s4=new String();
label1: for(int i=0;i< 5;i++)
{int n=-1,l=0,p=0;
for(int j=1;j< =d;j++)
{
n++;
l++;
//int p=0;
if(n>s3.length()-1)
{
char e=s3.charAt(p);
if(l==d)
{
s3.deleteCharAt(p);
//String s4=new String();
s4=s3.substring(p,s3.length());
////System.out.println(s4);
s3.delete(p,s3.length());
////System.out.println(s3);
s3.insert(0,s4);
////System.out.println(s3);
break;
}
else{ p++;
if(p==s3.length())
{p=0;
}
}
}
else
{
char e=s3.charAt(n);
if(l==d)
{
s3.deleteCharAt(n);
s4=s3.substring(n,s3.length());
////System.out.println(s4);
s3.delete(n,s3.length());
////System.out.println(s3);
s3.insert(0,s4);
////System.out.println(s3);
break;
}
//break;
}
}
}
////System.out.println(s3);
char result=s3.charAt(0);
switch(result){
case 'f':
System.out.println(second+" is ur Friend");
break;
case 'l':
System.out.println(second+" is ur Love");
break;
case 'a':
System.out.println(second+" is ur Affection");
break;
case 'm':
System.out.println("u r going to marry "+ second);
break;
case 'e':
System.out.println(second + " is ur Enemy");
break;
case 's':
System.out.println(second +" is ur Sister");
break;
}
}
}
FAQ's in C.
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
Section 1. Declarations and Initializations
1.1: How do you decide which integer type to use?
A: If you might need large values (tens of thousands), use long.
Otherwise, if space is very important, use short. Otherwise,
use int.
1.4: What should the 64-bit type on a machine that can support it?
A: C9X specifies long long.
1.7: What's the best way to declare and define global variables?
A: The best arrangement is to place each definition in some
relevant .c file, with an external declaration in a header file.
1.11: What does extern mean in a function declaration?
A: Nothing, really; the keyword extern is optional here.
1.12: What's the auto keyword good for?
A: Nothing.
1.14: I can't seem to define a linked list node which contains a
pointer to itself.
A: Structures in C can certainly contain pointers to themselves;
the discussion and example in section 6.5 of K&R make this
clear. Problems arise if an attempt is made to define (and use)
a typedef in the midst of such a declaration; avoid this.
1.21: How do I declare an array of N pointers to functions returning
pointers to functions returning pointers to characters?
A: char *(*(*a[N])())();
Using a chain of typedefs, or the cdecl program, makes these
declarations easier.
1.22: How can I declare a function that returns a pointer to a
function of its own type?
A: You can't quite do it directly. Use a cast, or wrap a struct
around the pointer and return that.
1.25: My compiler is complaining about an invalid redeclaration of a
function, but I only define it once.
A: Calling an undeclared function declares it implicitly as
returning int.
1.25b: What's the right declaration for main()?
A: See questions 11.12a to 11.15.
1.30: What am I allowed to assume about the initial values
of variables which are not explicitly initialized?
A: Uninitialized variables with "static" duration start out as 0,
as if the programmer had initialized them. Variables with
"automatic" duration, and dynamically-allocated memory, start
out containing garbage (with the exception of calloc).
1.31: Why can't I initialize a local array with a string?
A: Perhaps you have a pre-ANSI compiler.
1.31b: What's wrong with "char *p = malloc(10);" ?
A: Function calls are not allowed in initializers for global or
static variables.
1.32: What is the difference between char a[] = "string"; and
char *p = "string"; ?
A: The first declares an initialized and modifiable array; the
second declares a pointer initialized to a not-necessarily-
modifiable constant string.
1.34: How do I initialize a pointer to a function?
A: Use something like "extern int func(); int (*fp)() = func;" .
C Questions...Try them !!
Predict the output or error(s) for the following:
1.
void main()
{
int const * p=5;
printf("%d",++(*p));
}
Answer:
Compiler error: Cannot modify a constant value.
Explanation:
p is a pointer to a "constant integer". But we tried to change the value of the "constant integer".
2.
main()
{
char s[ ]="man";
int i;
for(i=0;s[ i ];i++)
printf("\n%c%c%c%c",s[ i ],*(s+i),*(i+s),i[s]);
}
Answer:
mmmm
aaaa
nnnn
Explanation:
s[i], *(i+s), *(s+i), i[s] are all different ways of expressing the same idea. Generally array name is the base address for that array. Here s is the base address. i is the index number/displacement from the base address. So, indirecting it with * is same as s[i]. i[s] may be surprising. But in the case of C it is same as s[i].
3.
main()
{
float me = 1.1;
double you = 1.1;
if(me==you)
printf("I love U");
else
printf("I hate U");
}
Answer:
I hate U
Explanation:
For floating point numbers (float, double, long double) the values cannot be predicted exactly. Depending on the number of bytes, the precession with of the value represented varies. Float takes 4 bytes and long double takes 10 bytes. So float stores 0.9 with less precision than long double.
Rule of Thumb:
Never compare or at-least be cautious when using floating point numbers with relational operators (== , >, <, <=, >=,!= ) .
4.
main()
{
static int var = 5;
printf("%d ",var--);
if(var)
main();
}
Answer:
5 4 3 2 1
Explanation:
When static storage class is given, it is initialized once. The change in the value of a static variable is retained even between the function calls. Main is also treated like any other ordinary function, which can be called recursively.
5.
main()
{
int c[ ]={2.8,3.4,4,6.7,5};
int j,*p=c,*q=c;
for(j=0;j<5;j++) {
printf(" %d ",*c);
++q; }
for(j=0;j<5;j++){
printf(" %d ",*p);
++p; }
}
Answer:
2 2 2 2 2 2 3 4 6 5
Explanation:
Initially pointer c is assigned to both p and q. In the first loop, since only q is incremented and not c , the value 2 will be printed 5 times. In second loop p itself is incremented. So the values 2 3 4 6 5 will be printed.
6.
main()
{
extern int i;
i=20;
printf("%d",i);
}
Answer:
Linker Error : Undefined symbol '_i'
Explanation:
extern storage class in the following declaration,
extern int i;
specifies to the compiler that the memory for i is allocated in some other program and that address will be given to the current program at the time of linking. But linker finds that no other variable of name i is available in any other program with memory space allocated for it. Hence a linker error has occurred .
7.
main()
{
int i=-1,j=-1,k=0,l=2,m;
m=i++&&j++&&k++||l++;
printf("%d %d %d %d %d",i,j,k,l,m);
}
Answer:
0 0 1 3 1
Explanation :
Logical operations always give a result of 1 or 0 . And also the logical AND (&&) operator has higher priority over the logical OR (||) operator. So the expression ‘i++ && j++ && k++’ is executed first. The result of this expression is 0 (-1 && -1 && 0 = 0). Now the expression is 0 || 2 which evaluates to 1 (because OR operator always gives 1 except for ‘0 || 0’ combination- for which it gives 0). So the value of m is 1. The values of other variables are also incremented by 1.
8.
main()
{
char *p;
printf("%d %d ",sizeof(*p),sizeof(p));
}
Answer:
1 2
Explanation:
The sizeof() operator gives the number of bytes taken by its operand. P is a character pointer, which needs one byte for storing its value (a character). Hence sizeof(*p) gives a value of 1. Since it needs two bytes to store the address of the character pointer sizeof(p) gives 2.
9.
main()
{
int i=3;
switch(i)
{
default:printf("zero");
case 1: printf("one");
break;
case 2:printf("two");
break;
case 3: printf("three");
break;
}
}
Answer :
three
Explanation :
The default case can be placed anywhere inside the loop. It is executed only when all other cases doesn't match.
10.
main()
{
printf("%x",-1<<4);
}
Answer:
fff0
Explanation :
-1 is internally represented as all 1's. When left shifted four times the least significant 4 bits are filled with 0's.The %x format specifier specifies that the integer value be printed as a hexadecimal value.
11.
main()
{
char string[]="Hello World";
display(string);
}
void display(char *string)
{
printf("%s",string);
}
Answer:
Compiler Error : Type mismatch in redeclaration of function display
Explanation :
In third line, when the function display is encountered, the compiler doesn't know anything about the function display. It assumes the arguments and return types to be integers, (which is the default type). When it sees the actual function display, the arguments and type contradicts with what it has assumed previously. Hence a compile time error occurs.
12.
main()
{
int c=- -2;
printf("c=%d",c);
}
Answer:
c=2;
Explanation:
Here unary minus (or negation) operator is used twice. Same maths rules applies, ie. minus * minus= plus.
Note:
However you cannot give like --2. Because -- operator can only be applied to variables as a decrement operator (eg., i--). 2 is a constant and not a variable.
13.
#define int char
main()
{
int i=65;
printf("sizeof(i)=%d",sizeof(i));
}
Answer:
sizeof(i)=1
Explanation:
Since the #define replaces the string int by the macro char
1.
void main()
{
int const * p=5;
printf("%d",++(*p));
}
Answer:
Compiler error: Cannot modify a constant value.
Explanation:
p is a pointer to a "constant integer". But we tried to change the value of the "constant integer".
2.
main()
{
char s[ ]="man";
int i;
for(i=0;s[ i ];i++)
printf("\n%c%c%c%c",s[ i ],*(s+i),*(i+s),i[s]);
}
Answer:
mmmm
aaaa
nnnn
Explanation:
s[i], *(i+s), *(s+i), i[s] are all different ways of expressing the same idea. Generally array name is the base address for that array. Here s is the base address. i is the index number/displacement from the base address. So, indirecting it with * is same as s[i]. i[s] may be surprising. But in the case of C it is same as s[i].
3.
main()
{
float me = 1.1;
double you = 1.1;
if(me==you)
printf("I love U");
else
printf("I hate U");
}
Answer:
I hate U
Explanation:
For floating point numbers (float, double, long double) the values cannot be predicted exactly. Depending on the number of bytes, the precession with of the value represented varies. Float takes 4 bytes and long double takes 10 bytes. So float stores 0.9 with less precision than long double.
Rule of Thumb:
Never compare or at-least be cautious when using floating point numbers with relational operators (== , >, <, <=, >=,!= ) .
4.
main()
{
static int var = 5;
printf("%d ",var--);
if(var)
main();
}
Answer:
5 4 3 2 1
Explanation:
When static storage class is given, it is initialized once. The change in the value of a static variable is retained even between the function calls. Main is also treated like any other ordinary function, which can be called recursively.
5.
main()
{
int c[ ]={2.8,3.4,4,6.7,5};
int j,*p=c,*q=c;
for(j=0;j<5;j++) {
printf(" %d ",*c);
++q; }
for(j=0;j<5;j++){
printf(" %d ",*p);
++p; }
}
Answer:
2 2 2 2 2 2 3 4 6 5
Explanation:
Initially pointer c is assigned to both p and q. In the first loop, since only q is incremented and not c , the value 2 will be printed 5 times. In second loop p itself is incremented. So the values 2 3 4 6 5 will be printed.
6.
main()
{
extern int i;
i=20;
printf("%d",i);
}
Answer:
Linker Error : Undefined symbol '_i'
Explanation:
extern storage class in the following declaration,
extern int i;
specifies to the compiler that the memory for i is allocated in some other program and that address will be given to the current program at the time of linking. But linker finds that no other variable of name i is available in any other program with memory space allocated for it. Hence a linker error has occurred .
7.
main()
{
int i=-1,j=-1,k=0,l=2,m;
m=i++&&j++&&k++||l++;
printf("%d %d %d %d %d",i,j,k,l,m);
}
Answer:
0 0 1 3 1
Explanation :
Logical operations always give a result of 1 or 0 . And also the logical AND (&&) operator has higher priority over the logical OR (||) operator. So the expression ‘i++ && j++ && k++’ is executed first. The result of this expression is 0 (-1 && -1 && 0 = 0). Now the expression is 0 || 2 which evaluates to 1 (because OR operator always gives 1 except for ‘0 || 0’ combination- for which it gives 0). So the value of m is 1. The values of other variables are also incremented by 1.
8.
main()
{
char *p;
printf("%d %d ",sizeof(*p),sizeof(p));
}
Answer:
1 2
Explanation:
The sizeof() operator gives the number of bytes taken by its operand. P is a character pointer, which needs one byte for storing its value (a character). Hence sizeof(*p) gives a value of 1. Since it needs two bytes to store the address of the character pointer sizeof(p) gives 2.
9.
main()
{
int i=3;
switch(i)
{
default:printf("zero");
case 1: printf("one");
break;
case 2:printf("two");
break;
case 3: printf("three");
break;
}
}
Answer :
three
Explanation :
The default case can be placed anywhere inside the loop. It is executed only when all other cases doesn't match.
10.
main()
{
printf("%x",-1<<4);
}
Answer:
fff0
Explanation :
-1 is internally represented as all 1's. When left shifted four times the least significant 4 bits are filled with 0's.The %x format specifier specifies that the integer value be printed as a hexadecimal value.
11.
main()
{
char string[]="Hello World";
display(string);
}
void display(char *string)
{
printf("%s",string);
}
Answer:
Compiler Error : Type mismatch in redeclaration of function display
Explanation :
In third line, when the function display is encountered, the compiler doesn't know anything about the function display. It assumes the arguments and return types to be integers, (which is the default type). When it sees the actual function display, the arguments and type contradicts with what it has assumed previously. Hence a compile time error occurs.
12.
main()
{
int c=- -2;
printf("c=%d",c);
}
Answer:
c=2;
Explanation:
Here unary minus (or negation) operator is used twice. Same maths rules applies, ie. minus * minus= plus.
Note:
However you cannot give like --2. Because -- operator can only be applied to variables as a decrement operator (eg., i--). 2 is a constant and not a variable.
13.
#define int char
main()
{
int i=65;
printf("sizeof(i)=%d",sizeof(i));
}
Answer:
sizeof(i)=1
Explanation:
Since the #define replaces the string int by the macro char
Fun with C++
Take the following code:
int i, n = 20;
for (i=0; i< n; i--)
{
cout << "x" << endl;
}
by changing only ONE character in the above code, meaning you cannot change 20 to 31, because you will have changed two characters, you can change 20 to 21, because you only changed the 0, do the following:
find 3 ways to make the above code print x 20 times (by changing only one character).
1) Write one line of code to swap the contents two variables without using a temp variable.
2) Write a program to print 1-100 and backward without using loops.
3)Write a C++ program to print out "Hello world" without using any ';'
For 2)
#include
void count(int n, int max)
{
std::cout <<<" "; if(n < n =" 100;">
int main(){
double a,b;
std::cout <<"Input a,b separated by space : "; std::cin >> a >>b;
a-=b=(a+=b)-b; //one line swapping +/-
std::cout <<"a= "<< b=" ">
}
3)
#include
int main(){
double a,b;
std::cout <<"Input a,b separated by space : "; std::cin >> a >>b;
a-=b=(a+=b)-b; //one line swapping +/-
std::cout <<"a= "<< b=" ">
}
1)
void main()
{
if(printf("Hello World!\n")){}
}
int i, n = 20;
for (i=0; i< n; i--)
{
cout << "x" << endl;
}
by changing only ONE character in the above code, meaning you cannot change 20 to 31, because you will have changed two characters, you can change 20 to 21, because you only changed the 0, do the following:
find 3 ways to make the above code print x 20 times (by changing only one character).
1) Write one line of code to swap the contents two variables without using a temp variable.
2) Write a program to print 1-100 and backward without using loops.
3)Write a C++ program to print out "Hello world" without using any ';'
For 2)
#include
void count(int n, int max)
{
std::cout <<<" "; if(n < n =" 100;">
int main(){
double a,b;
std::cout <<"Input a,b separated by space : "; std::cin >> a >>b;
a-=b=(a+=b)-b; //one line swapping +/-
std::cout <<"a= "<< b=" ">
}
3)
#include
int main(){
double a,b;
std::cout <<"Input a,b separated by space : "; std::cin >> a >>b;
a-=b=(a+=b)-b; //one line swapping +/-
std::cout <<"a= "<< b=" ">
}
1)
void main()
{
if(printf("Hello World!\n")){}
}
A Basic Guide to Internet
The Internet is a computer network made up of thousands of networks worldwide. No one knows exactly how many computers are connected to the Internet. It is certain, however, that these number in the millions.
No one is in charge of the Internet. There are organizations which develop technical aspects of this network and set standards for creating applications on it, but no governing body is in control. The Internet backbone, through which Internet traffic flows, is owned by private companies.
All computers on the Internet communicate with one another using the Transmission Control Protocol/Internet Protocol suite, abbreviated to TCP/IP. Computers on the Internet use a client/server architecture. This means that the remote server machine provides files and services to the user's local client machine. Software can be installed on a client computer to take advantage of the latest access technology.
An Internet user has access to a wide variety of services: electronic mail, file transfer, vast information resources, interest group membership, interactive collaboration, multimedia displays, real-time broadcasting, shopping opportunities, breaking news, and much more.
The Internet consists primarily of a variety of access protocols. Many of these protocols feature programs that allow users to search for and retrieve material made available by the protocol.
--------------------------------------------------------------------------------
COMPONENTS OF THE INTERNET
--------------------------------------------------------------------------------
WORLD WIDE WEB
The World Wide Web (abbreviated as the Web or WWW) is a system of Internet servers that supports hypertext to access several Internet protocols on a single interface. Almost every protocol type available on the Internet is accessible on the Web. This includes e-mail, FTP, Telnet, and Usenet News. In addition to these, the World Wide Web has its own protocol: HyperText Transfer Protocol, or HTTP. These protocols will be explained later in this document.
The World Wide Web provides a single interface for accessing all these protocols. This creates a convenient and user-friendly environment. It is no longer necessary to be conversant in these protocols within separate, command-level environments. The Web gathers together these protocols into a single system. Because of this feature, and because of the Web's ability to work with multimedia and advanced programming languages, the Web is the fastest-growing component of the Internet.
The operation of the Web relies primarily on hypertext as its means of information retrieval. HyperText is a document containing words that connect to other documents. These words are called links and are selectable by the user. A single hypertext document can contain links to many documents. In the context of the Web, words or graphics may serve as links to other documents, images, video, and sound. Links may or may not follow a logical path, as each connection is programmed by the creator of the source document. Overall, the Web contains a complex virtual web of connections among a vast number of documents, graphics, videos, and sounds.
Producing hypertext for the Web is accomplished by creating documents with a language called HyperText Markup Language, or HTML. With HTML, tags are placed within the text to accomplish document formatting, visual features such as font size, italics and bold, and the creation of hypertext links. Graphics and multimedia may also be incorporated into an HTML document. HTML is an evolving language, with new tags being added as each upgrade of the language is developed and released. The World Wide Web Consortium (W3C), led by Web founder Tim Berners-Lee, coordinates the efforts of standardizing HTML. The W3C now calls the language XHTML and considers it to be an application of the XML language standard.
The World Wide Web consists of files, called pages or home pages, containing links to documents and resources throughout the Internet.
The Web provides a vast array of experiences including multimedia presentations, real-time collaboration, interactive pages, radio and television broadcasts, and the automatic "push" of information to a client computer. Programming languages such as Java, JavaScript, Visual Basic, Cold Fusion and XML are extending the capabilities of the Web. A growing amount of information on the Web is served dynamically from content stored in databases. The Web is therefore not a fixed entity, but one that is in a constant state of development and flux.
For more complete information about the World Wide Web, see Understanding The World Wide Web.
E-MAIL
Electronic mail, or e-mail, allows computer users locally and worldwide to exchange messages. Each user of e-mail has a mailbox address to which messages are sent. Messages sent through e-mail can arrive within a matter of seconds.
A powerful aspect of e-mail is the option to send electronic files to a person's e-mail address. Non-ASCII files, known as binary files, may be attached to e-mail messages. These files are referred to as MIME attachments.MIME stands for Multimedia Internet Mail Extension, and was developed to help e-mail software handle a variety of file types. For example, a document created in Microsoft Word can be attached to an e-mail message and retrieved by the recipient with the appropriate e-mail program. Many e-mail programs, including Eudora, Netscape Messenger, and Microsoft Outlook, offer the ability to read files written in HTML, which is itself a MIME type.
TELNET
Telnet is a program that allows you to log into computers on the Internet and use online databases, library catalogs, chat services, and more. There are no graphics in Telnet sessions, just text. To Telnet to a computer, you must know its address. This can consist of words (locis.loc.gov) or numbers (140.147.254.3). Some services require you to connect to a specific port on the remote computer. In this case, type the port number after the Internet address. Example: telnet nri.reston.va.us 185.
Telnet is available on the World Wide Web. Probably the most common Web-based resources available through Telnet have been library catalogs, though most catalogs have since migrated to the Web. A link to a Telnet resource may look like any other link, but it will launch a Telnet session to make the connection. A Telnet program must be installed on your local computer and configured to your Web browser in order to work.
With the increasing popularity of the Web, Telnet has become less frequently used as a means of access to information on the Internet.
FTP
FTP stands for File Transfer Protocol. This is both a program and the method used to transfer files between computers. Anonymous FTP is an option that allows users to transfer files from thousands of host computers on the Internet to their personal computer account. FTP sites contain books, articles, software, games, images, sounds, multimedia, course work, data sets, and more.
If your computer is directly connected to the Internet via an Ethernet cable, you can use one of several PC software programs, such as WS_FTP for Windows, to conduct a file transfer.
FTP transfers can be performed on the World Wide Web without the need for special software. In this case, the Web browser will suffice. Whenever you download software from a Web site to your local machine, you are using FTP. You can also retrieve FTP files via search engines such as FtpFind, located at /http://www.ftpfind.com/. This option is easiest because you do not need to know FTP program commands.
E-MAIL DISCUSSION GROUPS
One of the benefits of the Internet is the opportunity it offers to people worldwide to communicate via e-mail. The Internet is home to a large community of individuals who carry out active discussions organized around topic-oriented forums distributed by e-mail. These are administered by software programs. Probably the most common program is the listserv.
A great variety of topics are covered by listservs, many of them academic in nature. When you subscribe to a listserv, messages from other subscribers are automatically sent to your electronic mailbox. You subscribe to a listserv by sending an e-mail message to a computer program called a listserver. Listservers are located on computer networks throughout the world. This program handles subscription information and distributes messages to and from subscribers. You must have a e-mail account to participate in a listserv discussion group. Visit Tile.net at /http://tile.net/ to see an example of a site that offers a searchablecollection of e-mail discussion groups.
Majordomo and Listproc are two other programs that administer e-mail discussion groups. The commands for subscribing to and managing your list memberships are similar to those of listserv.
USENET NEWS
Usenet News is a global electronic bulletin board system in which millions of computer users exchange information on a vast range of topics. The major difference between Usenet News and e-mail discussion groups is the fact that Usenet messages are stored on central computers, and users must connect to these computers to read or download the messages posted to these groups. This is distinct from e-mail distribution, in which messages arrive in the electronic mailboxes of each list member.
Usenet itself is a set of machines that exchanges messages, or articles, from Usenet discussion forums, called newsgroups. Usenet administrators control their own sites, and decide which (if any) newsgroups to sponsor and which remote newsgroups to allow into the system.
There are thousands of Usenet newsgroups in existence. While many are academic in nature, numerous newsgroups are organized around recreational topics. Much serious computer-related work takes place in Usenet discussions. A small number of e-mail discussion groups also exist as Usenet newsgroups.
The Usenet newsfeed can be read by a variety of newsreader software programs. For example, the Netscape suite comes with a newsreader program called Messenger. Newsreaders are also available as standalone products.
FAQ, RFC, FYI
FAQ stands for Frequently Asked Questions. These are periodic postings to Usenet newsgroups that contain a wealth of information related to the topic of the newsgroup. Many FAQs are quite extensive. FAQs are available by subscribing to individual Usenet newsgroups. A Web-based collection of FAQ resources has been collected by The Internet FAQ Consortium and is available at /http://www.faqs.org/.
RFC stands for Request for Comments. These are documents created by and distributed to the Internet community to help define the nuts and bolts of the Internet. They contain both technical specifications and general information.
FYI stands for For Your Information. These notes are a subset of RFCs and contain information of interest to new Internet users.
Links to indexes of all three of these information resources are available on the University Libraries Web site at /http://library.albany.edu/reference/faqs.html.
CHAT & INSTANT MESSENGING
Chat programs allow users on the Internet to communicate with each other by typing in real time. They are sometimes included as a feature of a Web site, where users can log into the "chat room" to exchange comments and information about the topics addressed on the site. Chat may take other, more wide-ranging forms. For example, America Online is well known for sponsoring a number of topical chat rooms.
Internet Relay Chat (IRC) is a service through which participants can communicate to each other on hundreds of channels. These channels are usually based on specific topics. While many topics are frivolous, substantive conversations are also taking place. To access IRC, you must use an IRC software program.
A variation of chat is the phenomenon of instant messenging. With instant messenging, a user on the Web can contact another user currently logged in and type a conversation. Most famous is America Online's Instant Messenger. ICQ, MSN and Yahoo are other commonly-used chat programs.
Other types of real-time communication are addressed in the tutorial Understanding the World Wide Web.
MUD/MUSH/MOO/MUCK/DUM/MUSE
MUD stands for Multi User Dimension. MUDs, and their variations listed above, are multi-user virtual reality games based on simulated worlds. Traditionally text based, graphical MUDs now exist. There are MUDs of all kinds on the Internet, and many can be joined free of charge. For more information, read one of the FAQs devoted to MUDs available at the FAQ site at
No one is in charge of the Internet. There are organizations which develop technical aspects of this network and set standards for creating applications on it, but no governing body is in control. The Internet backbone, through which Internet traffic flows, is owned by private companies.
All computers on the Internet communicate with one another using the Transmission Control Protocol/Internet Protocol suite, abbreviated to TCP/IP. Computers on the Internet use a client/server architecture. This means that the remote server machine provides files and services to the user's local client machine. Software can be installed on a client computer to take advantage of the latest access technology.
An Internet user has access to a wide variety of services: electronic mail, file transfer, vast information resources, interest group membership, interactive collaboration, multimedia displays, real-time broadcasting, shopping opportunities, breaking news, and much more.
The Internet consists primarily of a variety of access protocols. Many of these protocols feature programs that allow users to search for and retrieve material made available by the protocol.
--------------------------------------------------------------------------------
COMPONENTS OF THE INTERNET
--------------------------------------------------------------------------------
WORLD WIDE WEB
The World Wide Web (abbreviated as the Web or WWW) is a system of Internet servers that supports hypertext to access several Internet protocols on a single interface. Almost every protocol type available on the Internet is accessible on the Web. This includes e-mail, FTP, Telnet, and Usenet News. In addition to these, the World Wide Web has its own protocol: HyperText Transfer Protocol, or HTTP. These protocols will be explained later in this document.
The World Wide Web provides a single interface for accessing all these protocols. This creates a convenient and user-friendly environment. It is no longer necessary to be conversant in these protocols within separate, command-level environments. The Web gathers together these protocols into a single system. Because of this feature, and because of the Web's ability to work with multimedia and advanced programming languages, the Web is the fastest-growing component of the Internet.
The operation of the Web relies primarily on hypertext as its means of information retrieval. HyperText is a document containing words that connect to other documents. These words are called links and are selectable by the user. A single hypertext document can contain links to many documents. In the context of the Web, words or graphics may serve as links to other documents, images, video, and sound. Links may or may not follow a logical path, as each connection is programmed by the creator of the source document. Overall, the Web contains a complex virtual web of connections among a vast number of documents, graphics, videos, and sounds.
Producing hypertext for the Web is accomplished by creating documents with a language called HyperText Markup Language, or HTML. With HTML, tags are placed within the text to accomplish document formatting, visual features such as font size, italics and bold, and the creation of hypertext links. Graphics and multimedia may also be incorporated into an HTML document. HTML is an evolving language, with new tags being added as each upgrade of the language is developed and released. The World Wide Web Consortium (W3C), led by Web founder Tim Berners-Lee, coordinates the efforts of standardizing HTML. The W3C now calls the language XHTML and considers it to be an application of the XML language standard.
The World Wide Web consists of files, called pages or home pages, containing links to documents and resources throughout the Internet.
The Web provides a vast array of experiences including multimedia presentations, real-time collaboration, interactive pages, radio and television broadcasts, and the automatic "push" of information to a client computer. Programming languages such as Java, JavaScript, Visual Basic, Cold Fusion and XML are extending the capabilities of the Web. A growing amount of information on the Web is served dynamically from content stored in databases. The Web is therefore not a fixed entity, but one that is in a constant state of development and flux.
For more complete information about the World Wide Web, see Understanding The World Wide Web.
Electronic mail, or e-mail, allows computer users locally and worldwide to exchange messages. Each user of e-mail has a mailbox address to which messages are sent. Messages sent through e-mail can arrive within a matter of seconds.
A powerful aspect of e-mail is the option to send electronic files to a person's e-mail address. Non-ASCII files, known as binary files, may be attached to e-mail messages. These files are referred to as MIME attachments.MIME stands for Multimedia Internet Mail Extension, and was developed to help e-mail software handle a variety of file types. For example, a document created in Microsoft Word can be attached to an e-mail message and retrieved by the recipient with the appropriate e-mail program. Many e-mail programs, including Eudora, Netscape Messenger, and Microsoft Outlook, offer the ability to read files written in HTML, which is itself a MIME type.
TELNET
Telnet is a program that allows you to log into computers on the Internet and use online databases, library catalogs, chat services, and more. There are no graphics in Telnet sessions, just text. To Telnet to a computer, you must know its address. This can consist of words (locis.loc.gov) or numbers (140.147.254.3). Some services require you to connect to a specific port on the remote computer. In this case, type the port number after the Internet address. Example: telnet nri.reston.va.us 185.
Telnet is available on the World Wide Web. Probably the most common Web-based resources available through Telnet have been library catalogs, though most catalogs have since migrated to the Web. A link to a Telnet resource may look like any other link, but it will launch a Telnet session to make the connection. A Telnet program must be installed on your local computer and configured to your Web browser in order to work.
With the increasing popularity of the Web, Telnet has become less frequently used as a means of access to information on the Internet.
FTP
FTP stands for File Transfer Protocol. This is both a program and the method used to transfer files between computers. Anonymous FTP is an option that allows users to transfer files from thousands of host computers on the Internet to their personal computer account. FTP sites contain books, articles, software, games, images, sounds, multimedia, course work, data sets, and more.
If your computer is directly connected to the Internet via an Ethernet cable, you can use one of several PC software programs, such as WS_FTP for Windows, to conduct a file transfer.
FTP transfers can be performed on the World Wide Web without the need for special software. In this case, the Web browser will suffice. Whenever you download software from a Web site to your local machine, you are using FTP. You can also retrieve FTP files via search engines such as FtpFind, located at /http://www.ftpfind.com/. This option is easiest because you do not need to know FTP program commands.
E-MAIL DISCUSSION GROUPS
One of the benefits of the Internet is the opportunity it offers to people worldwide to communicate via e-mail. The Internet is home to a large community of individuals who carry out active discussions organized around topic-oriented forums distributed by e-mail. These are administered by software programs. Probably the most common program is the listserv.
A great variety of topics are covered by listservs, many of them academic in nature. When you subscribe to a listserv, messages from other subscribers are automatically sent to your electronic mailbox. You subscribe to a listserv by sending an e-mail message to a computer program called a listserver. Listservers are located on computer networks throughout the world. This program handles subscription information and distributes messages to and from subscribers. You must have a e-mail account to participate in a listserv discussion group. Visit Tile.net at /http://tile.net/ to see an example of a site that offers a searchablecollection of e-mail discussion groups.
Majordomo and Listproc are two other programs that administer e-mail discussion groups. The commands for subscribing to and managing your list memberships are similar to those of listserv.
USENET NEWS
Usenet News is a global electronic bulletin board system in which millions of computer users exchange information on a vast range of topics. The major difference between Usenet News and e-mail discussion groups is the fact that Usenet messages are stored on central computers, and users must connect to these computers to read or download the messages posted to these groups. This is distinct from e-mail distribution, in which messages arrive in the electronic mailboxes of each list member.
Usenet itself is a set of machines that exchanges messages, or articles, from Usenet discussion forums, called newsgroups. Usenet administrators control their own sites, and decide which (if any) newsgroups to sponsor and which remote newsgroups to allow into the system.
There are thousands of Usenet newsgroups in existence. While many are academic in nature, numerous newsgroups are organized around recreational topics. Much serious computer-related work takes place in Usenet discussions. A small number of e-mail discussion groups also exist as Usenet newsgroups.
The Usenet newsfeed can be read by a variety of newsreader software programs. For example, the Netscape suite comes with a newsreader program called Messenger. Newsreaders are also available as standalone products.
FAQ, RFC, FYI
FAQ stands for Frequently Asked Questions. These are periodic postings to Usenet newsgroups that contain a wealth of information related to the topic of the newsgroup. Many FAQs are quite extensive. FAQs are available by subscribing to individual Usenet newsgroups. A Web-based collection of FAQ resources has been collected by The Internet FAQ Consortium and is available at /http://www.faqs.org/.
RFC stands for Request for Comments. These are documents created by and distributed to the Internet community to help define the nuts and bolts of the Internet. They contain both technical specifications and general information.
FYI stands for For Your Information. These notes are a subset of RFCs and contain information of interest to new Internet users.
Links to indexes of all three of these information resources are available on the University Libraries Web site at /http://library.albany.edu/reference/faqs.html.
CHAT & INSTANT MESSENGING
Chat programs allow users on the Internet to communicate with each other by typing in real time. They are sometimes included as a feature of a Web site, where users can log into the "chat room" to exchange comments and information about the topics addressed on the site. Chat may take other, more wide-ranging forms. For example, America Online is well known for sponsoring a number of topical chat rooms.
Internet Relay Chat (IRC) is a service through which participants can communicate to each other on hundreds of channels. These channels are usually based on specific topics. While many topics are frivolous, substantive conversations are also taking place. To access IRC, you must use an IRC software program.
A variation of chat is the phenomenon of instant messenging. With instant messenging, a user on the Web can contact another user currently logged in and type a conversation. Most famous is America Online's Instant Messenger. ICQ, MSN and Yahoo are other commonly-used chat programs.
Other types of real-time communication are addressed in the tutorial Understanding the World Wide Web.
MUD/MUSH/MOO/MUCK/DUM/MUSE
MUD stands for Multi User Dimension. MUDs, and their variations listed above, are multi-user virtual reality games based on simulated worlds. Traditionally text based, graphical MUDs now exist. There are MUDs of all kinds on the Internet, and many can be joined free of charge. For more information, read one of the FAQs devoted to MUDs available at the FAQ site at
10 reasons why PCs crash U must Know
Fatal error: the system has become unstable or is busy," it says. "Enter to return to Windows or press Control-Alt-Delete to restart your computer. If you do this you will lose any unsaved information in all open applications."
You have just been struck by the Blue Screen of Death. Anyone who uses Mcft Windows will be familiar with this. What can you do? More importantly, how can you prevent it happening?
1 Hardware conflict
The number one reason why Windows crashes is hardware conflict. Each hardware device communicates to other devices through an interrupt request channel (IRQ). These are supposed to be unique for each device.
For example, a printer usually connects internally on IRQ 7. The keyboard usually uses IRQ 1 and the floppy disk drive IRQ 6. Each device will try to hog a single IRQ for itself.
If there are a lot of devices, or if they are not installed properly, two of them may end up sharing the same IRQ number. When the user tries to use both devices at the same time, a crash can happen. The way to check if your computer has a hardware conflict is through the following route:
* Start-Settings-Control Panel-System-Device Manager.
Often if a device has a problem a yellow '!' appears next to its description in the Device Manager. Highlight Computer (in the Device Manager) and press Properties to see the IRQ numbers used by your computer. If the IRQ number appears twice, two devices may be using it.
Sometimes a device might share an IRQ with something described as 'IRQ holder for PCI steering'. This can be ignored. The best way to fix this problem is to remove the problem device and reinstall it.
Sometimes you may have to find more recent drivers on the internet to make the device function properly. A good resource is www.driverguide.com. If the device is a soundcard, or a modem, it can often be fixed by moving it to a different slot on the motherboard (be careful about opening your computer, as you may void the warranty).
When working inside a computer you should switch it off, unplug the mains lead and touch an unpainted metal surface to discharge any static electricity.
To be fair to Mcft, the problem with IRQ numbers is not of its making. It is a legacy problem going back to the first PC designs using the IBM 8086 chip. Initially there were only eight IRQs. Today there are 16 IRQs in a PC. It is easy to run out of them. There are plans to increase the number of IRQs in future designs.
2 Bad Ram
Ram (random-access memory) problems might bring on the blue screen of death with a message saying Fatal Exception Error. A fatal error indicates a serious hardware problem. Sometimes it may mean a part is damaged and will need replacing.
But a fatal error caused by Ram might be caused by a mismatch of chips. For example, mixing 70-nanosecond (70ns) Ram with 60ns Ram will usually force the computer to run all the Ram at the slower speed. This will often crash the machine if the Ram is overworked.
One way around this problem is to enter the BIOS settings and increase the wait state of the Ram. This can make it more stable. Another way to troubleshoot a suspected Ram problem is to rearrange the Ram chips on the motherboard, or take some of them out. Then try to repeat the circumstances that caused the crash. When handling Ram try not to touch the gold connections, as they can be easily damaged.
Parity error messages also refer to Ram. Modern Ram chips are either parity (ECC) or non parity (non-ECC). It is best not to mix the two types, as this can be a cause of trouble.
EMM386 error messages refer to memory problems but may not be connected to bad Ram. This may be due to free memory problems often linked to old Dos-based programmes.
3 BIOS settings
Every motherboard is supplied with a range of chipset settings that are decided in the factory. A common way to access these settings is to press the F2 or delete button during the first few seconds of a boot-up.
Once inside the BIOS, great care should be taken. It is a good idea to write down on a piece of paper all the settings that appear on the screen. That way, if you change something and the computer becomes more unstable, you will know what settings to revert to.
A common BIOS error concerns the CAS latency. This refers to the Ram. Older EDO (extended data out) Ram has a CAS latency of 3. Newer SDRam has a CAS latency of 2. Setting the wrong figure can cause the Ram to lock up and freeze the computer's display.
Mcft Windows is better at allocating IRQ numbers than any BIOS. If possible set the IRQ numbers to Auto in the BIOS. This will allow Windows to allocate the IRQ numbers (make sure the BIOS setting for Plug and Play OS is switched to 'yes' to allow Windows to do this.).
4 Hard disk drives
After a few weeks, the information on a hard disk drive starts to become piecemeal or fragmented. It is a good idea to defragment the hard disk every week or so, to prevent the disk from causing a screen freeze. Go to
* Start-Programs-Accessories-System Tools-Disk Defragmenter
This will start the procedure. You will be unable to write data to the hard drive (to save it) while the disk is defragmenting, so it is a good idea to schedule the procedure for a period of inactivity using the Task Scheduler.
The Task Scheduler should be one of the small icons on the bottom right of the Windows opening page (the desktop).
Some lockups and screen freezes caused by hard disk problems can be solved by reducing the read-ahead optimisation. This can be adjusted by going to
* Start-Settings-Control Panel-System Icon-Performance-File System-Hard Disk.
Hard disks will slow down and crash if they are too full. Do some housekeeping on your hard drive every few months and free some space on it. Open the Windows folder on the C drive and find the Temporary Internet Files folder. Deleting the contents (not the folder) can free a lot of space.
Empty the Recycle Bin every week to free more space. Hard disk drives should be scanned every week for errors or bad sectors. Go to
* Start-Programs-Accessories-System Tools-ScanDisk
Otherwise assign the Task Scheduler to perform this operation at night when the computer is not in use.
5 Fatal OE exceptions and VXD errors
Fatal OE exception errors and VXD errors are often caused by video card problems.
These can often be resolved easily by reducing the resolution of the video display. Go to
* Start-Settings-Control Panel-Display-Settings
Here you should slide the screen area bar to the left. Take a look at the colour settings on the left of that window. For most desktops, high colour 16-bit depth is adequate.
If the screen freezes or you experience system lockups it might be due to the video card. Make sure it does not have a hardware conflict. Go to
* Start-Settings-Control Panel-System-Device Manager
Here, select the + beside Display Adapter. A line of text describing your video card should appear. Select it (make it blue) and press properties. Then select Resources and select each line in the window. Look for a message that says No Conflicts.
If you have video card hardware conflict, you will see it here. Be careful at this point and make a note of everything you do in case you make things worse.
The way to resolve a hardware conflict is to uncheck the Use Automatic Settings box and hit the Change Settings button. You are searching for a setting that will display a No Conflicts message.
Another useful way to resolve video problems is to go to
* Start-Settings-Control Panel-System-Performance-Graphics
Here you should move the Hardware Acceleration slider to the left. As ever, the most common cause of problems relating to graphics cards is old or faulty drivers (a driver is a small piece of software used by a computer to communicate with a device).
Look up your video card's manufacturer on the internet and search for the most recent drivers for it.
6 Viruses
Often the first sign of a virus infection is instability. Some viruses erase the boot sector of a hard drive, making it impossible to start. This is why it is a good idea to create a Windows start-up disk. Go to
* Start-Settings-Control Panel-Add/Remove Programs
Here, look for the Start Up Disk tab. Virus protection requires constant vigilance.
A virus scanner requires a list of virus signatures in order to be able to identify viruses. These signatures are stored in a DAT file. DAT files should be updated weekly from the website of your antivirus software manufacturer.
An excellent antivirus programme is McAfee VirusScan by Network Associates ( www.nai.com). Another is Norton AntiVirus 2000, made by Symantec ( www.symantec.com).
7 Printers
The action of sending a document to print creates a bigger file, often called a postscript file.
Printers have only a small amount of memory, called a buffer. This can be easily overloaded. Printing a document also uses a considerable amount of CPU power. This will also slow down the computer's performance.
If the printer is trying to print unusual characters, these might not be recognised, and can crash the computer. Sometimes printers will not recover from a crash because of confusion in the buffer. A good way to clear the buffer is to unplug the printer for ten seconds. Booting up from a powerless state, also called a cold boot, will restore the printer's default settings and you may be able to carry on.
8 Software
A common cause of computer crash is faulty or badly-installed software. Often the problem can be cured by uninstalling the software and then reinstalling it. Use Norton Uninstall or Uninstall Shield to remove an application from your system properly. This will also remove references to the programme in the System Registry and leaves the way clear for a completely fresh copy.
The System Registry can be corrupted by old references to obsolete software that you thought was uninstalled. Use Reg Cleaner by Jouni Vuorio to clean up the System Registry and remove obsolete entries. It works on Windows 95, Windows 98, Windows 98 SE (Second Edition), Windows Millennium Edition (ME), NT4 and Windows 2000.
Read the instructions and use it carefully so you don't do permanent damage to the Registry. If the Registry is damaged you will have to reinstall your operating system. Reg Cleaner can be obtained from www.jv16.org
Often a Windows problem can be resolved by entering Safe Mode. This can be done during start-up. When you see the message "Starting Windows" press F4. This should take you into Safe Mode.
Safe Mode loads a minimum of drivers. It allows you to find and fix problems that prevent Windows from loading properly.
Sometimes installing Windows is difficult because of unsuitable BIOS settings. If you keep getting SUWIN error messages (Windows setup) during the Windows installation, then try entering the BIOS and disabling the CPU internal cache. Try to disable the Level 2 (L2) cache if that doesn't work.
Remember to restore all the BIOS settings back to their former settings following installation.
9 Overheating
Central processing units (CPUs) are usually equipped with fans to keep them cool. If the fan fails or if the CPU gets old it may start to overheat and generate a particular kind of error called a kernel error. This is a common problem in chips that have been overclocked to operate at higher speeds than they are supposed to.
One remedy is to get a bigger better fan and install it on top of the CPU. Specialist cooling fans/heatsinks are available from www.computernerd.com or www.coolit.com
CPU problems can often be fixed by disabling the CPU internal cache in the BIOS. This will make the machine run more slowly, but it should also be more stable.
10 Power supply problems
With all the new construction going on around the country the steady supply of electricity has become disrupted. A power surge or spike can crash a computer as easily as a power cut.
If this has become a nuisance for you then consider buying a uninterrupted power supply (UPS). This will give you a clean power supply when there is electricity, and it will give you a few minutes to perform a controlled shutdown in case of a power cut.
It is a good investment if your data are critical, because a power cut will cause any unsaved data to be lost.
You have just been struck by the Blue Screen of Death. Anyone who uses Mcft Windows will be familiar with this. What can you do? More importantly, how can you prevent it happening?
1 Hardware conflict
The number one reason why Windows crashes is hardware conflict. Each hardware device communicates to other devices through an interrupt request channel (IRQ). These are supposed to be unique for each device.
For example, a printer usually connects internally on IRQ 7. The keyboard usually uses IRQ 1 and the floppy disk drive IRQ 6. Each device will try to hog a single IRQ for itself.
If there are a lot of devices, or if they are not installed properly, two of them may end up sharing the same IRQ number. When the user tries to use both devices at the same time, a crash can happen. The way to check if your computer has a hardware conflict is through the following route:
* Start-Settings-Control Panel-System-Device Manager.
Often if a device has a problem a yellow '!' appears next to its description in the Device Manager. Highlight Computer (in the Device Manager) and press Properties to see the IRQ numbers used by your computer. If the IRQ number appears twice, two devices may be using it.
Sometimes a device might share an IRQ with something described as 'IRQ holder for PCI steering'. This can be ignored. The best way to fix this problem is to remove the problem device and reinstall it.
Sometimes you may have to find more recent drivers on the internet to make the device function properly. A good resource is www.driverguide.com. If the device is a soundcard, or a modem, it can often be fixed by moving it to a different slot on the motherboard (be careful about opening your computer, as you may void the warranty).
When working inside a computer you should switch it off, unplug the mains lead and touch an unpainted metal surface to discharge any static electricity.
To be fair to Mcft, the problem with IRQ numbers is not of its making. It is a legacy problem going back to the first PC designs using the IBM 8086 chip. Initially there were only eight IRQs. Today there are 16 IRQs in a PC. It is easy to run out of them. There are plans to increase the number of IRQs in future designs.
2 Bad Ram
Ram (random-access memory) problems might bring on the blue screen of death with a message saying Fatal Exception Error. A fatal error indicates a serious hardware problem. Sometimes it may mean a part is damaged and will need replacing.
But a fatal error caused by Ram might be caused by a mismatch of chips. For example, mixing 70-nanosecond (70ns) Ram with 60ns Ram will usually force the computer to run all the Ram at the slower speed. This will often crash the machine if the Ram is overworked.
One way around this problem is to enter the BIOS settings and increase the wait state of the Ram. This can make it more stable. Another way to troubleshoot a suspected Ram problem is to rearrange the Ram chips on the motherboard, or take some of them out. Then try to repeat the circumstances that caused the crash. When handling Ram try not to touch the gold connections, as they can be easily damaged.
Parity error messages also refer to Ram. Modern Ram chips are either parity (ECC) or non parity (non-ECC). It is best not to mix the two types, as this can be a cause of trouble.
EMM386 error messages refer to memory problems but may not be connected to bad Ram. This may be due to free memory problems often linked to old Dos-based programmes.
3 BIOS settings
Every motherboard is supplied with a range of chipset settings that are decided in the factory. A common way to access these settings is to press the F2 or delete button during the first few seconds of a boot-up.
Once inside the BIOS, great care should be taken. It is a good idea to write down on a piece of paper all the settings that appear on the screen. That way, if you change something and the computer becomes more unstable, you will know what settings to revert to.
A common BIOS error concerns the CAS latency. This refers to the Ram. Older EDO (extended data out) Ram has a CAS latency of 3. Newer SDRam has a CAS latency of 2. Setting the wrong figure can cause the Ram to lock up and freeze the computer's display.
Mcft Windows is better at allocating IRQ numbers than any BIOS. If possible set the IRQ numbers to Auto in the BIOS. This will allow Windows to allocate the IRQ numbers (make sure the BIOS setting for Plug and Play OS is switched to 'yes' to allow Windows to do this.).
4 Hard disk drives
After a few weeks, the information on a hard disk drive starts to become piecemeal or fragmented. It is a good idea to defragment the hard disk every week or so, to prevent the disk from causing a screen freeze. Go to
* Start-Programs-Accessories-System Tools-Disk Defragmenter
This will start the procedure. You will be unable to write data to the hard drive (to save it) while the disk is defragmenting, so it is a good idea to schedule the procedure for a period of inactivity using the Task Scheduler.
The Task Scheduler should be one of the small icons on the bottom right of the Windows opening page (the desktop).
Some lockups and screen freezes caused by hard disk problems can be solved by reducing the read-ahead optimisation. This can be adjusted by going to
* Start-Settings-Control Panel-System Icon-Performance-File System-Hard Disk.
Hard disks will slow down and crash if they are too full. Do some housekeeping on your hard drive every few months and free some space on it. Open the Windows folder on the C drive and find the Temporary Internet Files folder. Deleting the contents (not the folder) can free a lot of space.
Empty the Recycle Bin every week to free more space. Hard disk drives should be scanned every week for errors or bad sectors. Go to
* Start-Programs-Accessories-System Tools-ScanDisk
Otherwise assign the Task Scheduler to perform this operation at night when the computer is not in use.
5 Fatal OE exceptions and VXD errors
Fatal OE exception errors and VXD errors are often caused by video card problems.
These can often be resolved easily by reducing the resolution of the video display. Go to
* Start-Settings-Control Panel-Display-Settings
Here you should slide the screen area bar to the left. Take a look at the colour settings on the left of that window. For most desktops, high colour 16-bit depth is adequate.
If the screen freezes or you experience system lockups it might be due to the video card. Make sure it does not have a hardware conflict. Go to
* Start-Settings-Control Panel-System-Device Manager
Here, select the + beside Display Adapter. A line of text describing your video card should appear. Select it (make it blue) and press properties. Then select Resources and select each line in the window. Look for a message that says No Conflicts.
If you have video card hardware conflict, you will see it here. Be careful at this point and make a note of everything you do in case you make things worse.
The way to resolve a hardware conflict is to uncheck the Use Automatic Settings box and hit the Change Settings button. You are searching for a setting that will display a No Conflicts message.
Another useful way to resolve video problems is to go to
* Start-Settings-Control Panel-System-Performance-Graphics
Here you should move the Hardware Acceleration slider to the left. As ever, the most common cause of problems relating to graphics cards is old or faulty drivers (a driver is a small piece of software used by a computer to communicate with a device).
Look up your video card's manufacturer on the internet and search for the most recent drivers for it.
6 Viruses
Often the first sign of a virus infection is instability. Some viruses erase the boot sector of a hard drive, making it impossible to start. This is why it is a good idea to create a Windows start-up disk. Go to
* Start-Settings-Control Panel-Add/Remove Programs
Here, look for the Start Up Disk tab. Virus protection requires constant vigilance.
A virus scanner requires a list of virus signatures in order to be able to identify viruses. These signatures are stored in a DAT file. DAT files should be updated weekly from the website of your antivirus software manufacturer.
An excellent antivirus programme is McAfee VirusScan by Network Associates ( www.nai.com). Another is Norton AntiVirus 2000, made by Symantec ( www.symantec.com).
7 Printers
The action of sending a document to print creates a bigger file, often called a postscript file.
Printers have only a small amount of memory, called a buffer. This can be easily overloaded. Printing a document also uses a considerable amount of CPU power. This will also slow down the computer's performance.
If the printer is trying to print unusual characters, these might not be recognised, and can crash the computer. Sometimes printers will not recover from a crash because of confusion in the buffer. A good way to clear the buffer is to unplug the printer for ten seconds. Booting up from a powerless state, also called a cold boot, will restore the printer's default settings and you may be able to carry on.
8 Software
A common cause of computer crash is faulty or badly-installed software. Often the problem can be cured by uninstalling the software and then reinstalling it. Use Norton Uninstall or Uninstall Shield to remove an application from your system properly. This will also remove references to the programme in the System Registry and leaves the way clear for a completely fresh copy.
The System Registry can be corrupted by old references to obsolete software that you thought was uninstalled. Use Reg Cleaner by Jouni Vuorio to clean up the System Registry and remove obsolete entries. It works on Windows 95, Windows 98, Windows 98 SE (Second Edition), Windows Millennium Edition (ME), NT4 and Windows 2000.
Read the instructions and use it carefully so you don't do permanent damage to the Registry. If the Registry is damaged you will have to reinstall your operating system. Reg Cleaner can be obtained from www.jv16.org
Often a Windows problem can be resolved by entering Safe Mode. This can be done during start-up. When you see the message "Starting Windows" press F4. This should take you into Safe Mode.
Safe Mode loads a minimum of drivers. It allows you to find and fix problems that prevent Windows from loading properly.
Sometimes installing Windows is difficult because of unsuitable BIOS settings. If you keep getting SUWIN error messages (Windows setup) during the Windows installation, then try entering the BIOS and disabling the CPU internal cache. Try to disable the Level 2 (L2) cache if that doesn't work.
Remember to restore all the BIOS settings back to their former settings following installation.
9 Overheating
Central processing units (CPUs) are usually equipped with fans to keep them cool. If the fan fails or if the CPU gets old it may start to overheat and generate a particular kind of error called a kernel error. This is a common problem in chips that have been overclocked to operate at higher speeds than they are supposed to.
One remedy is to get a bigger better fan and install it on top of the CPU. Specialist cooling fans/heatsinks are available from www.computernerd.com or www.coolit.com
CPU problems can often be fixed by disabling the CPU internal cache in the BIOS. This will make the machine run more slowly, but it should also be more stable.
10 Power supply problems
With all the new construction going on around the country the steady supply of electricity has become disrupted. A power surge or spike can crash a computer as easily as a power cut.
If this has become a nuisance for you then consider buying a uninterrupted power supply (UPS). This will give you a clean power supply when there is electricity, and it will give you a few minutes to perform a controlled shutdown in case of a power cut.
It is a good investment if your data are critical, because a power cut will cause any unsaved data to be lost.
10 Fast and Free Security Enhancements
Before you spend a dime on security, there are many precautions you can take that will protect you against the most common threats.
1. Check Windows Update and Office Update regularly
2. Install a personal firewall.
3. Install a free spyware blocker.
4. Block pop-up spam messages in Windows XP by disabling the Windows Messenger service (this is unrelated to the instant messaging program). Open Control Panel | Administrative Tools | Services and you'll see Messenger. Right-click and go to Properties. Set Start-up Type to Disabled and press the Stop button. Bye-bye, spam pop-ups! Any good firewall will also stop them.
5. Use strong passwords and change them periodically. Passwords should have at least seven characters; use letters and numbers and have at least one symbol. A decent example would be f8izKro@l. This will make it much harder for anyone to gain access to your accounts.
6. If you're using Outlook or Outlook Express, use the current version or one with the Outlook Security Update installed. The update and current versions patch numerous vulnerabilities.
7. Buy antivirus software and keep it up to date. If you're not willing to pay, try Grisoft AVG Free Edition (Grisoft Inc., w*w.grisoft.com).
8. If you have a wireless network, turn on the security features: Use MAC filtering, turn off SSID broadcast, and even use WEP with the biggest key you can get. For more, check out our wireless section or see the expanded coverage in Your Unwired World in our next issue.
9. Join a respectable e-mail security list, such as the one found at our own Security Supersite at _http://security.ziffdavis.com, so that you learn about emerging threats quickly and can take proper precautions.
10. Be skeptical of things on the Internet. Don't assume that e-mail "From:" a particular person is actually from that person until you have further reason to believe it's that person. Don't assume that an attachment is what it says it is. Don't give out your password to anyone, even if that person claims to be from "support.
1. Check Windows Update and Office Update regularly
2. Install a personal firewall.
3. Install a free spyware blocker.
4. Block pop-up spam messages in Windows XP by disabling the Windows Messenger service (this is unrelated to the instant messaging program). Open Control Panel | Administrative Tools | Services and you'll see Messenger. Right-click and go to Properties. Set Start-up Type to Disabled and press the Stop button. Bye-bye, spam pop-ups! Any good firewall will also stop them.
5. Use strong passwords and change them periodically. Passwords should have at least seven characters; use letters and numbers and have at least one symbol. A decent example would be f8izKro@l. This will make it much harder for anyone to gain access to your accounts.
6. If you're using Outlook or Outlook Express, use the current version or one with the Outlook Security Update installed. The update and current versions patch numerous vulnerabilities.
7. Buy antivirus software and keep it up to date. If you're not willing to pay, try Grisoft AVG Free Edition (Grisoft Inc., w*w.grisoft.com).
8. If you have a wireless network, turn on the security features: Use MAC filtering, turn off SSID broadcast, and even use WEP with the biggest key you can get. For more, check out our wireless section or see the expanded coverage in Your Unwired World in our next issue.
9. Join a respectable e-mail security list, such as the one found at our own Security Supersite at _http://security.ziffdavis.com, so that you learn about emerging threats quickly and can take proper precautions.
10. Be skeptical of things on the Internet. Don't assume that e-mail "From:" a particular person is actually from that person until you have further reason to believe it's that person. Don't assume that an attachment is what it says it is. Don't give out your password to anyone, even if that person claims to be from "support.
20 Great Google Secrets
Google is clearly the best general-purpose search engine on the Web (see
www.pcmag.com/searchengines
But most people don't use it to its best advantage. Do you just plug in a keyword or two and hope for the best? That may be the quickest way to search, but with more than 3 billion pages in Google's index, it's still a struggle to pare results to a manageable number.
But Google is an remarkably powerful tool that can ease and enhance your Internet exploration. Google's search options go beyond simple keywords, the Web, and even its own programmers. Let's look at some of Google's lesser-known options.
Syntax Search Tricks
Using a special syntax is a way to tell Google that you want to restrict your searches to certain elements or characteristics of Web pages. Google has a fairly complete list of its syntax elements at
www.google.com/help/operators.html
. Here are some advanced operators that can help narrow down your search results.
Intitle: at the beginning of a query word or phrase (intitle:"Three Blind Mice") restricts your search results to just the titles of Web pages.
Intext: does the opposite of intitle:, searching only the body text, ignoring titles, links, and so forth. Intext: is perfect when what you're searching for might commonly appear in URLs. If you're looking for the term HTML, for example, and you don't want to get results such as
www.mysite.com/index.html
, you can enter intext:html.
Link: lets you see which pages are linking to your Web page or to another page you're interested in. For example, try typing in
link:http://www.pcmag.com
Try using site: (which restricts results to top-level domains) with intitle: to find certain types of pages. For example, get scholarly pages about Mark Twain by searching for intitle:"Mark Twain"site:edu. Experiment with mixing various elements; you'll develop several strategies for finding the stuff you want more effectively. The site: command is very helpful as an alternative to the mediocre search engines built into many sites.
Swiss Army Google
Google has a number of services that can help you accomplish tasks you may never have thought to use Google for. For example, the new calculator feature
(www.google.com/help/features.html#calculator)
lets you do both math and a variety of conversions from the search box. For extra fun, try the query "Answer to life the universe and everything."
Let Google help you figure out whether you've got the right spelling—and the right word—for your search. Enter a misspelled word or phrase into the query box (try "thre blund mise") and Google may suggest a proper spelling. This doesn't always succeed; it works best when the word you're searching for can be found in a dictionary. Once you search for a properly spelled word, look at the results page, which repeats your query. (If you're searching for "three blind mice," underneath the search window will appear a statement such as Searched the web for "three blind mice.") You'll discover that you can click on each word in your search phrase and get a definition from a dictionary.
Suppose you want to contact someone and don't have his phone number handy. Google can help you with that, too. Just enter a name, city, and state. (The city is optional, but you must enter a state.) If a phone number matches the listing, you'll see it at the top of the search results along with a map link to the address. If you'd rather restrict your results, use rphonebook: for residential listings or bphonebook: for business listings. If you'd rather use a search form for business phone listings, try Yellow Search
(www.buzztoolbox.com/google/yellowsearch.shtml).
Extended Googling
Google offers several services that give you a head start in focusing your search. Google Groups
(http://groups.google.com)
indexes literally millions of messages from decades of discussion on Usenet. Google even helps you with your shopping via two tools: Froogle
CODE
(http://froogle.google.com),
which indexes products from online stores, and Google Catalogs
CODE
(http://catalogs.google.com),
which features products from more 6,000 paper catalogs in a searchable index. And this only scratches the surface. You can get a complete list of Google's tools and services at
www.google.com/options/index.html
You're probably used to using Google in your browser. But have you ever thought of using Google outside your browser?
Google Alert
(www.googlealert.com)
monitors your search terms and e-mails you information about new additions to Google's Web index. (Google Alert is not affiliated with Google; it uses Google's Web services API to perform its searches.) If you're more interested in news stories than general Web content, check out the beta version of Google News Alerts
(www.google.com/newsalerts).
This service (which is affiliated with Google) will monitor up to 50 news queries per e-mail address and send you information about news stories that match your query. (Hint: Use the intitle: and source: syntax elements with Google News to limit the number of alerts you get.)
Google on the telephone? Yup. This service is brought to you by the folks at Google Labs
(http://labs.google.com),
a place for experimental Google ideas and features (which may come and go, so what's there at this writing might not be there when you decide to check it out). With Google Voice Search
(http://labs1.google.com/gvs.html),
you dial the Voice Search phone number, speak your keywords, and then click on the indicated link. Every time you say a new search term, the results page will refresh with your new query (you must have JavaScript enabled for this to work). Remember, this service is still in an experimental phase, so don't expect 100 percent success.
In 2002, Google released the Google API (application programming interface), a way for programmers to access Google's search engine results without violating the Google Terms of Service. A lot of people have created useful (and occasionally not-so-useful but interesting) applications not available from Google itself, such as Google Alert. For many applications, you'll need an API key, which is available free from
CODE
www.google.com/apis
. See the figures for two more examples, and visit
www.pcmag.com/solutions
for more.
Thanks to its many different search properties, Google goes far beyond a regular search engine. Give the tricks in this article a try. You'll be amazed at how many different ways Google can improve your Internet searching.
Online Extra: More Google Tips
Here are a few more clever ways to tweak your Google searches.
Search Within a Timeframe
Daterange: (start date–end date). You can restrict your searches to pages that were indexed within a certain time period. Daterange: searches by when Google indexed a page, not when the page itself was created. This operator can help you ensure that results will have fresh content (by using recent dates), or you can use it to avoid a topic's current-news blizzard and concentrate only on older results. Daterange: is actually more useful if you go elsewhere to take advantage of it, because daterange: requires Julian dates, not standard Gregorian dates. You can find converters on the Web (such as
CODE
http://aa.usno.navy.mil/data/docs/JulianDate.html
excl.gif No Active Links, Read the Rules - Edit by Ninja excl.gif
), but an easier way is to do a Google daterange: search by filling in a form at
www.researchbuzz.com/toolbox/goofresh.shtml or www.faganfinder.com/engines/google.shtml
. If one special syntax element is good, two must be better, right? Sometimes. Though some operators can't be mixed (you can't use the link: operator with anything else) many can be, quickly narrowing your results to a less overwhelming number.
More Google API Applications
Staggernation.com offers three tools based on the Google API. The Google API Web Search by Host (GAWSH) lists the Web hosts of the results for a given query
(www.staggernation.com/gawsh/).
When you click on the triangle next to each host, you get a list of results for that host. The Google API Relation Browsing Outliner (GARBO) is a little more complicated: You enter a URL and choose whether you want pages that related to the URL or linked to the URL
(www.staggernation.com/garbo/).
Click on the triangle next to an URL to get a list of pages linked or related to that particular URL. CapeMail is an e-mail search application that allows you to send an e-mail to google@capeclear.com with the text of your query in the subject line and get the first ten results for that query back. Maybe it's not something you'd do every day, but if your cell phone does e-mail and doesn't do Web browsing, this is a very handy address to know.
www.pcmag.com/searchengines
But most people don't use it to its best advantage. Do you just plug in a keyword or two and hope for the best? That may be the quickest way to search, but with more than 3 billion pages in Google's index, it's still a struggle to pare results to a manageable number.
But Google is an remarkably powerful tool that can ease and enhance your Internet exploration. Google's search options go beyond simple keywords, the Web, and even its own programmers. Let's look at some of Google's lesser-known options.
Syntax Search Tricks
Using a special syntax is a way to tell Google that you want to restrict your searches to certain elements or characteristics of Web pages. Google has a fairly complete list of its syntax elements at
www.google.com/help/operators.html
. Here are some advanced operators that can help narrow down your search results.
Intitle: at the beginning of a query word or phrase (intitle:"Three Blind Mice") restricts your search results to just the titles of Web pages.
Intext: does the opposite of intitle:, searching only the body text, ignoring titles, links, and so forth. Intext: is perfect when what you're searching for might commonly appear in URLs. If you're looking for the term HTML, for example, and you don't want to get results such as
www.mysite.com/index.html
, you can enter intext:html.
Link: lets you see which pages are linking to your Web page or to another page you're interested in. For example, try typing in
link:http://www.pcmag.com
Try using site: (which restricts results to top-level domains) with intitle: to find certain types of pages. For example, get scholarly pages about Mark Twain by searching for intitle:"Mark Twain"site:edu. Experiment with mixing various elements; you'll develop several strategies for finding the stuff you want more effectively. The site: command is very helpful as an alternative to the mediocre search engines built into many sites.
Swiss Army Google
Google has a number of services that can help you accomplish tasks you may never have thought to use Google for. For example, the new calculator feature
(www.google.com/help/features.html#calculator)
lets you do both math and a variety of conversions from the search box. For extra fun, try the query "Answer to life the universe and everything."
Let Google help you figure out whether you've got the right spelling—and the right word—for your search. Enter a misspelled word or phrase into the query box (try "thre blund mise") and Google may suggest a proper spelling. This doesn't always succeed; it works best when the word you're searching for can be found in a dictionary. Once you search for a properly spelled word, look at the results page, which repeats your query. (If you're searching for "three blind mice," underneath the search window will appear a statement such as Searched the web for "three blind mice.") You'll discover that you can click on each word in your search phrase and get a definition from a dictionary.
Suppose you want to contact someone and don't have his phone number handy. Google can help you with that, too. Just enter a name, city, and state. (The city is optional, but you must enter a state.) If a phone number matches the listing, you'll see it at the top of the search results along with a map link to the address. If you'd rather restrict your results, use rphonebook: for residential listings or bphonebook: for business listings. If you'd rather use a search form for business phone listings, try Yellow Search
(www.buzztoolbox.com/google/yellowsearch.shtml).
Extended Googling
Google offers several services that give you a head start in focusing your search. Google Groups
(http://groups.google.com)
indexes literally millions of messages from decades of discussion on Usenet. Google even helps you with your shopping via two tools: Froogle
CODE
(http://froogle.google.com),
which indexes products from online stores, and Google Catalogs
CODE
(http://catalogs.google.com),
which features products from more 6,000 paper catalogs in a searchable index. And this only scratches the surface. You can get a complete list of Google's tools and services at
www.google.com/options/index.html
You're probably used to using Google in your browser. But have you ever thought of using Google outside your browser?
Google Alert
(www.googlealert.com)
monitors your search terms and e-mails you information about new additions to Google's Web index. (Google Alert is not affiliated with Google; it uses Google's Web services API to perform its searches.) If you're more interested in news stories than general Web content, check out the beta version of Google News Alerts
(www.google.com/newsalerts).
This service (which is affiliated with Google) will monitor up to 50 news queries per e-mail address and send you information about news stories that match your query. (Hint: Use the intitle: and source: syntax elements with Google News to limit the number of alerts you get.)
Google on the telephone? Yup. This service is brought to you by the folks at Google Labs
(http://labs.google.com),
a place for experimental Google ideas and features (which may come and go, so what's there at this writing might not be there when you decide to check it out). With Google Voice Search
(http://labs1.google.com/gvs.html),
you dial the Voice Search phone number, speak your keywords, and then click on the indicated link. Every time you say a new search term, the results page will refresh with your new query (you must have JavaScript enabled for this to work). Remember, this service is still in an experimental phase, so don't expect 100 percent success.
In 2002, Google released the Google API (application programming interface), a way for programmers to access Google's search engine results without violating the Google Terms of Service. A lot of people have created useful (and occasionally not-so-useful but interesting) applications not available from Google itself, such as Google Alert. For many applications, you'll need an API key, which is available free from
CODE
www.google.com/apis
. See the figures for two more examples, and visit
www.pcmag.com/solutions
for more.
Thanks to its many different search properties, Google goes far beyond a regular search engine. Give the tricks in this article a try. You'll be amazed at how many different ways Google can improve your Internet searching.
Online Extra: More Google Tips
Here are a few more clever ways to tweak your Google searches.
Search Within a Timeframe
Daterange: (start date–end date). You can restrict your searches to pages that were indexed within a certain time period. Daterange: searches by when Google indexed a page, not when the page itself was created. This operator can help you ensure that results will have fresh content (by using recent dates), or you can use it to avoid a topic's current-news blizzard and concentrate only on older results. Daterange: is actually more useful if you go elsewhere to take advantage of it, because daterange: requires Julian dates, not standard Gregorian dates. You can find converters on the Web (such as
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http://aa.usno.navy.mil/data/docs/JulianDate.html
excl.gif No Active Links, Read the Rules - Edit by Ninja excl.gif
), but an easier way is to do a Google daterange: search by filling in a form at
www.researchbuzz.com/toolbox/goofresh.shtml or www.faganfinder.com/engines/google.shtml
. If one special syntax element is good, two must be better, right? Sometimes. Though some operators can't be mixed (you can't use the link: operator with anything else) many can be, quickly narrowing your results to a less overwhelming number.
More Google API Applications
Staggernation.com offers three tools based on the Google API. The Google API Web Search by Host (GAWSH) lists the Web hosts of the results for a given query
(www.staggernation.com/gawsh/).
When you click on the triangle next to each host, you get a list of results for that host. The Google API Relation Browsing Outliner (GARBO) is a little more complicated: You enter a URL and choose whether you want pages that related to the URL or linked to the URL
(www.staggernation.com/garbo/).
Click on the triangle next to an URL to get a list of pages linked or related to that particular URL. CapeMail is an e-mail search application that allows you to send an e-mail to google@capeclear.com with the text of your query in the subject line and get the first ten results for that query back. Maybe it's not something you'd do every day, but if your cell phone does e-mail and doesn't do Web browsing, this is a very handy address to know.
END TASK
Some times u come across over few programs which never close for a long time and hang up.
Opening the taskmanager by alt+ctrl+del or else ctrl+shift+esc and ending the task might close the program.
but what if it also works late.
Here is the registry trick for it....
To make this work according to our need we will have to modify the registry.
First go to Start –> Run –> regedit.
Then navigate to the following key: HKEY_CURRENT_USER\Control Panel\Desktop
In the right side pane, find the key “WaitToKillAppTimeout”, double click it and set the time to wait for not responding applications to come back to normal. The time is in milliseconds. If you want to end the task immediately, give the value as 0.
Opening the taskmanager by alt+ctrl+del or else ctrl+shift+esc and ending the task might close the program.
but what if it also works late.
Here is the registry trick for it....
To make this work according to our need we will have to modify the registry.
First go to Start –> Run –> regedit.
Then navigate to the following key: HKEY_CURRENT_USER\Control Panel\Desktop
In the right side pane, find the key “WaitToKillAppTimeout”, double click it and set the time to wait for not responding applications to come back to normal. The time is in milliseconds. If you want to end the task immediately, give the value as 0.