Shut down returns to log in screen

[steinaro]

Hi, I am using Ubuntu 10.10. When I click on the shut down button the system logs me out returning to the log in screen. Why? And how can this be corrected?

I had this problem on my other computer and fixed it earlier but I forget what I did.

Thanks for your quick replies. As soon as I get this fixed I can take a nap (long day at work).