logging off user causes crash

[Cathy]

Can anyone tell me why logging off user would cause a
crash?

Just about everytime I log off, instead of going to the
welcome screen where another user can log on, the screen
goes black and the computer seems to stop responding. It
doesn't shut down, nor does it reboot.

Strangely enough, this doesn't happen when the other user
logs off. What the... am I doing wrong?

Any ideas would be appreciated.
Thanks

 

[me]

either no-one knows or no-one gives a stuff