I've been using ubuntu 11.04 for several months now...but today it just decided to quit on me. I temporarily switched my computer from a widescreen monitor to an older, square one...and I got the message that my computer was not capable of using unity. This is ridiculous, as I had not only been using unity for months previously. But, at any rate, it 'fell back' onto the classic desktop (running metacity).
Nothing I do in ccsm has any effect on the desktop because, duh, it's running metacity (for example disabling/re-enabling the unity plugin). Ctrl+Alt+F1 and unity --reset, unity --replace leaves me with a metacity desktop, only now without window borders. I've triple checked- when I log into ubuntu I log into the "Ubuntu" session, not the "Ubuntu Classic" session or anything like that. It's just that...Unity didn't like my square monitor and is now irreversibly broken.
I'm actually a fairly experienced Ubuntu user, but I don't know much about unity's workings, and so I'm rather stuck. Help?