1) Start > run > "regedit" (without the quotes of course)
2) Go to the key:
- HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\Windows NT\CurrentVersion\WPAEvents\OOBETimer
and double click on it. Then change some of the value data to ANYTHING. Delete some, add some letters. Close regedit.
3) Go to start > run > "%systemroot%\system32\oobe\msoobe.exe /a" (again, dont type the quotes)
4) The activation screen will come up, click on register over telephone, then click on CHANGE PRODUCT KEY, enter in this key: JG28K-H9Q7X-BH6W4-3PDCQ-6XBFJ.
5) Restart your computer and enjoy the validated XP !!!
Disclaimer: This article is for informational and educational purpose only, as most information is found on various part of Internet. Readers should contacts Microsoft if their licensed or OEM software cannot be validated or purchase genuine software.