Log off caused shut down

[Guest]

I had three user accounts active. I logged off (rather than switched) from
one and the PC shut down - or at least the screen went blank and nothing
would respond. It did not power off which it usually does on shut down (is a
Dell Dimension). I had to force power off and then restart the PC.

I have got XP Home.

 

[Guest]

Further to my original post: I had one user account active and logged off,
hoping to get to the initial user selection window, but the screen went dark
(but still alive, with a faint glow) and nothing would respond, as happened
before. Had to force power off manually.