How To Change The Serial Used In Winxp, And Valid For XP Corporate

Change Serial Number Used In Winxp

All you need to to click on Start open Run and type the command
regedit and [Enter]

Go to Hkey_Local_Machine
\Software\Microsoft\WindowNT
\CurrentVersion\WPAEvents,

On the right you have to double click on "oobetimer" and change at least one digit of the current value to deactivate the windows.

After that click "OK" and close the Registry editor

On Second Step you have to open Run again and type the following command:

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

and click "OK" or [Enter]

Now you will see the "Active Windows" window now.

Now check or choose the option for "Yes I want to telephone a customer service representative to active Windows" and click "Next"

Now you will click on the "Change Product Key" You don't need to enter any information on that screen 

After that you will type in the new key and click "Update"

The active Windows by phone window will reappear at this point, you have to close it by clicking the X in the upper right hand corner

Finally reboot your system and click on Start and open "Run" and type following command"

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

and click "OK" or [Enter]

If you see "Windows is already activated" then everything is OK. or if not Then read the command carefully