I have had a running 13.04 system for quite some time now. However, I hadn't tried to install the NVIDIA drivers on it. I also had a similar problem on a 12.10 system. In the past I resolved this problem by re-installing the whole system.
I attempted to install
nvidia-current from the repository, and for the most part it looked like it was successful, except that after reboot Unity was mostly borked. I could see the wallpaper and my Wine application icons on the desktop. No side-bar menu and no top panel and no response to the super-key. I could still do Ctl-Alt-T to get a terminal.
nvidia* thinking that would solve the problem. It DID NOT.
I thought I might just install another copy on a different partition, using the same home partition, then compare what might be different. That showed the same behavior!! So I created another account and when I logged into that voila, Unity is back to its original ugly(out of the box) self, in that account only.
So this suggests that rather than something buried deep in
/etc it is something in my
I doubt anyone can simply diagnose what is going on for me specifically, but can someone teach me to fish? Tell me what to look for to help diagnose what is happening. I have lots of stuff hidden and otherwise in my home directory, and there are all sorts of files in
/var/log. But which ones, and what to look for is more of what I need. On the other hand, if someone knows how to fix this specific problem, I can take the next one as a learning experience instead.