How-to set wallpaper image before login in Windows XP
This entry was posted on Jan 29 2008
Open up the registry and browse to:
HKEY_USERS\.Default\Control Panel\Desktop\
edit the Wallpaper key to point to where ever you have your wallpaper stored (eg. c:\windows\wallpaper.bmp). The file needs to be a .bmp to show up but that is all you should need to do.
After a restart the background will show up behind the login window assuming you are not using the welcome screen.
If a user logs in and then logs out their wallpaper will show up instead. But this is great to keep things looking the same when computers are restarted often.