How to Deactivate Windows XP Pro

The standard retail license for Windows XP requires you to activate the operating system after installing it. During the activation process, information about your computer is transmitted to Microsoft's servers, which links that computer to your copy of Windows. If you are selling your computer and want to keep your copy of Windows XP, or if you want to move the Windows XP installation to another computer, you will need to deactivate it on the first computer.

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Deactivate your copy of Windows XP

Step

Press the Windows logo key and "R" simultaneously. Windows opens a "Run" dialog box. Type "regedit" without quotation marks in the box and press "Enter." The registry editor appears.

Step

Navigate through the folders on the left side of the screen to browse to "HKEY_LOCAL_MACHINE," "Software," "Microsoft," "WindowsNT," "CurrentVersion" and "WPAEvents." Click the "WPAEvents" folder.

Step

Right-click "OOBETimer" on the right side of the window, and then click "Modify." A new window appears showing several hexadecimal values. The exact values are unique to each computer. For example, you might see a string such as "D5 FF D5 71 D6 8B 6A."

Step

Change any numeral displayed under "Value Data." For example, you might find the value "D5" and change it to "D6," or "8D" to "9D." You may change any numeral you like; the result will be the same. Because this registry key stores the Windows XP activation data, changing it deactivates the operating system.

Step

Click "OK" and close the registry editor. Windows is no longer activated.