After an automatic update of the kernel on my Ubuntu 16.04 x64 I've lost any possibility to login (login loop problem). So, with Mate env I've solved a nvidia problem and installed Gnome desktop.
After a reboot, I can`t change environment from Mate to Gnome or default Ubuntu. Because whenever I click "env change icon", any buttons showed, till I press Enter. When I just enter my password without changing env, I have Mate desktop.
The question is:
- how to repair login window? Or
- how to set desktop env to default Ubuntu with terminal from Mate?