One thing that I have come across with spybot is that, if you are not carefull and read everything that it came up with, you may, and will, delete important windows files. I know this by experience and deleted c:/windows.dll files and found out that it was spybot that got rid of them because it thought they were a threat. You can run a OS fix with your windows xp cd in safe mode. Boot into safe mode with your cd and look for the option to fix or restore you windows files. That may work, I have used that one before.