I updated to Ubuntu 12.10 today from 12.04 using the graphical update tool. Everything seemed to be fine until I went to open Nautilus, and it would not open. Bizarrely, I am able to open a file that I happen to have on my desktop, but when I click on the launcher, it never opens. When I enter 'nautilus' in the terminal, I get this: (nautilus:8557): Gdk-CRITICAL **: gdk_x11_display_get_xdisplay: assertion `GDK_IS_DISPLAY (display)' failed zsh: segmentation fault (core dumped) nautilus I am not a total novice with ubuntu or linux, but all I can tell is that there is some problem with X. Can someone please point me in the right direction as far as fixing this? I really don't want to have to do a fresh install. Thank you very much.