Welcome Screen login problems

[Guest Wilbur3]

My user account passwords are irradically cycling through one character at a

time on all three user accounts continuously until I finally interrupt it by

clicking a few times or if that doesn't work I use key strokes such as the

Esc button to stop it. I can then type in my password to log in and

everything works normal until I restart, shut down or log off. I have

scanned for viruses, spyware etc and nothing has shown up.