I just upgraded from 11.10 to 12.04 (yeah I did an upgrade and not a clean install) and am having a couple of issues. The most pressing issue is that 4 times out of 5 when I try to shutdown, everything seems to go as it should except the machine won't completely shutdown. Everything seems off, but my power light stays on and I can't start the machine again until I hold the power button in for a few seconds and kill the machine.
Has anyone else had this problem?
I looked about and found reference to a bug with Nvidia drivers and shutdown / restart problems in 12.04. The bug wasn't exactly the same as the problem I had, but it was similar. I updated my Nvidia driver to the one with (post release updates)(version current updates) next to it in the list of additional drivers and the problem seems to be fixed. Specifically the driver I'm now using is version 295.40
I'm going to wait a couple of days before marking this thread as solved.
The problem still exists.