Deactivate Windows

• 1). Click the "Start" button on the lower-left side of the screen and choose "Run" from the "Start" menu.
  
  
• 2). Type "regedit" in the "Open" window that appears and click "OK." Navigate to "HKEY_LOCAL_MACHINE\Software\Microsoft\WindowsNT\Current Version\WPAEvents."
  
  
• 3). Right-click "OOBETimer," then click "Modify" from the menu that appears. Change at least one digit of this value to deactivate Windows.
  
  

Re-Activate Windows With New Product Key

• 1). Click "Start" and select the "Run" option. Type "%systemroot%\system32\oobe\msoobe.exe /a" in the "Open" window, then click "OK."
  
  
• 2). Click the "Yes, I want to telephone a customer service representative to activate Windows" option when prompted, then click "Next."
  
  
• 3). Click on the "Change Product Key" option. Enter in a new key in the "New key" boxes, then select the "Update" option.
  
  
• 4). Repeat steps 1 and 2. If Windows has successfully activated with the new product key, you receive a "Windows is already activated. Click OK to exit" message. Click "OK."
  
  
• 5). Install any of the XP service packs you wish to install.