How Do I Activate The XP Product Key With The Use Of Activation Wizard?

First of all it's a serious warning here if you did any thing wrong in the registry during the modification in a registry editor or by third party software. If their any problem occurs during the modification then you must have to reinstall your operating system. Microsoft cannot guarantee that these kinds of problems can be solving after the problem occur and always modify the registry at your own risk. If you want to change the few volume licensing product keys then you can change it by activation wizard.

HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\Current Version\WPAEvents In the right pane, right-click OOBETimer, and then click Modify.

You must change at least one digit of this value to deactivate Windows. Click Start, and then click Run. In the Open box, type the following command, and then click OK.

%systemroot%\system32\oobe\msoobe.exe /a  

Then click yes, I want to telephone a customer service representative to activate Windows, and then click Next. Click change 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. To check the product key repeat steps to verify that Windows is activated. You receive the following message:  Windows is already activated. Click OK to exit. Click OK.  Install Windows XP SP2 or a later version of Windows XP.