Validate your copy of Windows XP for free - No download necessary

Here's the trick....

*Open Notepad and paste the following

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion] "CurrentBuild"="1.511.1 () (Obsolete data - do not use)" "ProductId"="55274-640-1011873-23081" "DigitalProductId"=hex:a4,00,00,00,03,00,00,00,35,35,32,37,34,2d,36,34,30,2d,\ 31,30,31,31,38,37,33,2d,32,33,30,38,31,00,2e,00,00,00,41,32,32,2d,30,30,30,\ 30,31,00,00,00,00,00,00,00,86,56,4e,4c,21,1b,2b,6a,a3,78,8e,8f,98,5c,00,00,\ 00,00,00,00,dd,da,47,41,cc,6b,06,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\ 00,00,00,00,00,00,00,00,00,00,00,38,31,30,32,36,00,00,00,00,00,00,00,b5,16,\ 00,00,83,83,1f,38,f8,01,00,00,f5,1c,00,00,00,00,00,00,00,00,00,00,00,00,00,\ 00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,66,e5,70,f3 "LicenseInfo"=hex:33,b7,21,c1,e5,e7,cd,4b,fd,7c,c6,35,51,fd,52,57,17,86,3e,18,\ d3,f4,8c,8e,35,32,7b,d1,43,8d,61,38,60,a4,ca,55,c9,9a,35,17,46,7a,4f,91,fc,\ 4a,d9,db,64,5c,c4,e2,0f,34,f3,ea
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\WPAEvents] "OOBETimer"=hex:ff,d5,71,d6,8b,6a,8d,6f,d5,33,93,fd


* Now save the file as License Key.reg (Note: The file name must contain the .reg extension)
* Double click the file that you created. It will ask for confirmation.
* Click Yes... And you are done.
* To see that it worked go to

http://www.microsoft.com/genuine/downloads/FAQ.aspx

and click on "Validate Windows"

Don't open Microsoft's site if ur Volume Serial No. is already blocked.
U can test it by installing Windows Media Player 11 / Internet Explorer 7.

This post was found on the net...but it was a gud one...