I am running an ubuntu/gnome3 environment. While running the upgrade manager on 12.04, I was informed that there was a distribution update but that it was partial. (whatever that means)

After a few failed attempts at updating through the manager, I decide to run sudo apt-get update && sudo apt-get update. The updates seem to work however, the close/maximize/minimize buttons of all windows have disappeared. I also can no longer use the Alt+Tab function.

I tried to post an image but I need more rep (sorry)

I have tried to run the updates again but nothing changes. I'm still very new at this. I would appreciate it if you could use simple terms to describe or ask questions.

Thanks in advance!