The crash traceback that apport collected is not detailed enough to debug. The error in the .xsessions-errors file looks to be not an X server error, but an error in one of the client programs.
python: ../../src/xcb_io.c:242: process_responses: Controletest '(((long) (dpy->last_request_read) - (long) (dpy->request)) <= 0)' faalt. apport-kde apport-kde X Error: BadWindow (invalid Window parameter) 3 Major opcode: 20 Minor opcode: 0 Resource id: 0x8200027 kdeinit4: preparing to launch /usr/lib/kde4/kio_file.so kdeinit4: preparing to launch /usr/lib/kde4/kio_thumbnail.so kdeinit4: preparing to launch /usr/lib/kde4/kio_thumbnail.so Empty input file findServiceByDesktopPath: /home/wim/.kde/share/apps/RecentDocuments/bug-report-xsession.odt.desktop not found kdeinit4: preparing to launch /usr/bin/ooffice libpng error: Read Error libpng error: Read Error libpng error: Read Error Not really sure what's going on but looks like the system is getting into a bad state and this leads X to crash. A better backtrace would help, although as this is using the nvidia proprietary driver it is not likely this can be achieved. I'll refile with the nvidia bugs for now. ** Package changed: xorg-server (Ubuntu) => nvidia-graphics-drivers-180 (Ubuntu) ** Changed in: nvidia-graphics-drivers-180 (Ubuntu) Status: New => Incomplete -- Xorg crashed with SIGSEGV https://bugs.launchpad.net/bugs/507719 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs