This sounds like a variation on the very old problem called (google it!)
XP CORRUPT PROFILE
Microsoft does not offer a cure. Just what to do next.
I have a weird problem with one of my clients. There are two ladies using a single Windows XP computer. They are both local admins. Person #1 can login without any problem.
Person #2 can only login if person #1 is already logged in. She does it via fast user switching.
If they both log off person #2 cannot login using the standard way.
Before you ask, I have change person #2's password and yes I typed in the right password.
Any ideas on what could be the problem?
Thank you very much,