How to change the Windows XP Product Key?

Changing the product key for your Windows XP installation involves two steps:

1. Deactivating your current product key

2. Entering a new product key and activating your Windows XP again.

• Click on Start and select Run. In the Run dialogue box, type in regedit (to edit the registry).
• Go to HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\Current Version\WPAEvents
• On the right-hand pane, right click on the binary value ODBETimer and selectModify. You will see a string of numbers and letters.
• Change at least one character or number to any value between A to F or 1 to 9 respectively. Doing this will make your current Windows product key invalid anddeactivates your Windows XP installation.
• To reactivate using the new Windows XP product key, type this command in theRun dialogue box: C:\windows\system32\oobe\msoobe.exe /a and hit<<Enter>> (This will start the Windows Product Activation Wizard.)
• Select the option “Yes, I want to telephone a Microsoft Customer Service Representative to activate windows” and click on Next
• In this screen select the option “Change Product Key” , type in the new product key and click on “Update” and exit the screen.
• If you are using Windows XP Professional or Home edition, you will be prompted to activate your Windows again.

Note:

If you wish to find out if your current Windows XP installation has been activated or not, use this command in the Run dialogue box: C:\windows\system32\oobe\msoobe.exe /a
If you wish to find out which version (& Service Pack) of Windows XP you are using, type this command in the Run dialogue box: winver and click OK or hit the <<Enter>> key.