SourSoother

I recently installed SpyBot S&D on my system. After not being able to delete some spyware, I tried to increase the vigilance of the program by adjusting some settings. After rebooting XP, I get the login welcome screen. After typing in the password (even with the other accounts), I log in. A split second later, I instantly logoff. I can't seem to break this cycle. Do I have to reformat C and reinstall Windows on my partitioned drive? Is there a better way? I'd appreciate any help! Thanks!