- Before you reinstall Windows, you'll need to make a copy of the system's product activation data. This is stored as a pair of files named WPA.BAK and WPA.DBL in the %SystemRoot%\System32 folder (usually \Windows\System32).
- If your existing copy of Windows is bootable, you can copy these files out normally. If not, you have to boot to the Recovery Console or use some other tool to copy out the files. The files are very small (only 15 K or so each) and can be copied to a floppy, another hard drive or anywhere else that you see fit.
- Reinstall Windows XP normally. You can reformat the hard drive when you do this, if you choose to do so.
- After the reinstallation is finished, reboot the computer in Safe Mode.
- Go to the %SystemRoot%\System32 folder
- and rename the WPA.BAK and WPA.DBL files to something else (_WPA.BAK_ and _WPA.DBL_ should work).
- Copy in the backed-up WPA.BAK and WPA.DBL files to that directory.
- Reboot normally. Your new installation of Windows should be activated.
Bear in mind that this is not a "hack" or a way of circumventing product activation altogether. It will only work if the PA data is being backed up from and then restored to the same system -- or one that does not have significantly different hardware than the original.
About the author: Serdar Yegulalp is editor of the Windows Power Users Newsletter. Check it out for the latest advice and musings on the world of Windows network administrators. He is also the author of the book Windows Server Undocumented Solutions.
More information on this topic:
- Tip: Discover the 'hidden' user control panel in Windows XP
- Topics: Windows XP
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This was first published in August 2006