Reinstall XP without activation

Ever needed to reinstall the OS on the same system and wondered if it'll still activate?

This lets you reinstall Windows XP without having to activate it again:

1. 
   Copy the file %systemroot%\system32\wpa.dbl (to removable media like floppy/CD if you plan to reformat the drive and do not have
2. Reinstall Windows XP
   
3. Copy the file back to %systemroot%\system32

This only works if you are reinstalling XP on the same hardware - it's not a mechanism to use the same copy of XP on another system and bypass activation.

Alternatively, (if setting up from a network source or creating a bootable CD) copy WPA.DBL to $$\OME$\$$\system32.

Activating during unattended installation
To activate Windows XP during an unattended installation, insert the following line in the [Unattend] section of your answer file (unattend.txt or winnt.sif):
AutoActivate = YES

Note: %systemroot% is a system variable that points to your Windows installation directory, usually C:\Windows.