Try below in terminal :
metacity --replace &
If it works add it to the "System" > "Prefences" > " Startup Applications" for self launch each time

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Thanks you so much.
- Visitor 28 weeks 5 days agoit helped me alot the information that I got here.
once again thanks you
Well, I was having same proplem myself, no close/minimize/maximize buttons. couldnt find right answer from the web, It took me awhile, but finally I noticed that my son had played with compiz settings... once again. And there wasn't "window frames" activated anymore, he must have accidently clicket it off, because wobbling windows where turned on, and it is right next to window frames.
- Visitor 38 weeks 2 days agoHope this helps someone, it did the trick for me anyway :)