How to restore XP activation status
How to restore XP activation status information after a reformat
Double-click My Computer, then double-click on the "C" drive.
Navigate to the C:\Windows\System32 folder.
Locate the files named "wpa.dbl" and "wpa.bak" and copy them to a safe location such as a USB key or CD.
Reformat your disk and reinstall Windows XP on your reformatted hard drive, click "No" when asked if you want to activate Windows.
Reboot your computer into SafeMode (press F8 as Windows is booting up to see the Windows
Advanced Options menu and select SAFEBOOT_OPTION=Minimal)
Double-click My Computer, then double-click on the "C" drive again.
Navigate to the C:\Windows\System32 folder again.
Locate the files named "wpa.dbl" and "wpa.bak" (if it exists) and rename them to "wpadbl.new" and "wpabak.new"
Copy your original "wpa.dbl" and "wpa.bak" files from your USB key, CD or DVD or other location into the C:\Windows\System32 folder
Restart your system.
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