Click Start, and then click Run.
In the Open box, type regedit, and then click OK.In the navigation pane, locate and then click the following registry key:
HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\Current Version\WPAEvents
In the topic pane, right-click OOBETimer, and then click Modify.
Change at least one digit of this value to deactivate Windows.
Reactivate Windows and add new product key
Click Start, and then click Run.
In the Open box, type the following command, and then click OK.
%systemroot%\system32\oobe\msoobe.exe /a
Click Yes, I want to telephone a customer service representative to activate Windows, and then click Next.
Click Change Product key.
Type the new product key in the New key boxes, and then click Update.
If you are returned to the previous window, click Remind me later, and then restart the computer.
Repeat steps 1 and 2 to verify that Windows is activated. You receive the following message:
Windows is already activated. Click OK to exit.
HCQ9D-TVCWX-X9QRG-J4B2Y-GR2TT
***************
These keys are for Windows XP Professional SP2 Volume License Edition
MRX3F-47B9T-2487J-KWKMF-RPWBY
QC986-27D34-6M3TY-JJXP9-TBGMD
CM3HY-26VYW-6JRYC-X66GX-JVY2D
DP7CM-PD6MC-6BKXT-M8JJ6-RPXGJ
F4297-RCWJP-P482C-YY23Y-XH8W3
HH7VV-6P3G9-82TWK-QKJJ3-MXR96
HCQ9D-TVCWX-X9QRG-J4B2Y-GR2TT
