Changing the Windows XP activation code

A while ago, there was a thread that included detailed instructions on how to change the activation code that Windows XP uses, without reinstalling the entire package.

Friends of mine used an activation key that worked, but which was evidently pirated. They now want me to help them apply service packs, etc, which I will only do if they get a legal copy of XP. They have done so, but they don’t want to lose all the custom work they’ve done.

A search here is useless because “XP” is only two letters long. But can anyone re-post the information here? How can I go in and change the code that they used to activate XP so that they’re now legal?

  • Rick

If the product key is what you mean, here’s some instructions I found a while ago from who knows where:

  1. Run the program
    and browse to the Registry key:
    HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\WPAEvents
    Then open the OOBETimer value for editing (double click it).
  2. Change the first pair of characters to 00. If you want to stop before
    changing your key and restarting, changing the pair back to its original
    value will ‘reactivate’ Windows, so make sure to remember it.
  3. Run the program
    %systemroot%\system32\oobe\msoobe.exe /a
  4. Select the second option (the one about telephoning) and hit Next.
  5. Select the button at the bottom to Change Product key, enter your new
    key and hit Update.
  6. Close both the activation program and regedit, then restart your computer.
      • There are instructions on the MS website KB on how to do this. I am too lazy to find them myself, but the reason was that the beta of XP was a free deal, but then you were supposed to buy a license to upgrade it or whatever–so MS provided a way to change the reg number. I don’t remember if they are any different fom that posted above.


Please note that these instructions will only work if you have a valid legal product key. Service Pack 1 will still recognize a pirated product key and will fail to install. Neither of these links offers you a product key, crack, or any other method to circumvent protection methods