I'm also experiencing this bug in 16.10 with Gnome PPA's installed though. It seemed to occur when I upgraded the kernel to 4.8.1 with synaptic. Since then I can only boot into a Wayland session and can't launch synaptic either, though I can install other package managers.
** Changed in: ubuntu-gnome Status: New => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1643370 Title: 17.04: Unable to login with regular "Gnome" or "Gnome Classic" shell/-session To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-gnome/+bug/1643370/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs