Maintenance Mode doesn’t go away

So, I updated my WordPress with 2.5.1, but the admin went really (really!) slow. So I installed the WordPress Automatic Upgrade Plugin and redid it. It gave a few errors, but the text said everything went okay. Then in the new window: The latest update is already installed, so I go further and I discover my site still says:

The Site is currently undergoing maintenance, Sorry for the inconvinience

WordPress Automatic Upgrade Plugin provided by Techie Buzz.

I can’t get it away, I redid a few times the automatic installation: it gave and error, so I do it the other way (with clicking), it gave also a few errors but it said everything went okay. But the maintenance mode is still up! I already deleted the plugin, but it still didn’t went away…

Could you guys explain me how I get this away? Thanks.