I am on a DELL Precision 5510 Ubuntu Edition with Ubuntu 14.04 as default installation. Today I upgraded from 14.04. to 16.04 as shown here
The upgrade went without any error messages. However, after reboot I cannot login via Login Manager (
lightdm by default?) anymore. While the password is accepted, the screen shortly prompts the desktop view for, say, a second and then immediately switches back to the login screen without further notice.
I can properly login via text console ( CTL + ALT + F1). So it is definitely not a password wrong issue.
I have read that this might have happened users before, see here. Difference with me is, that the screen after the login attempt is not completely black but it actually shows the desktop overview and even a system dialogue which I can't access because the loop follows to quickly.
What could be wrong here? How can I use my system again? Any help is much appreciated.