Hi Guys,
I yesterday did an apt update / apt upgrade.
After that, the next reboot offered me a login screen with a typical ubuntu wallpaper and nothing more. It is just stuck there and does nothing.
I did installed Ultimate Edition 5.0 XFCE four times yesterday to try to mitigate the thing. During the first installation, I ticked the choice to get the updates during the installation. When it rebooted, I came straight to the same problem. A wallpaper but no interface for login.
I installed again Ultimate Edition from scratch without network. Everything immediately ran fine. I did an image through clonezilla. Then I updated it again. Same problem.
I suspect something with lightdm which is among the updates. I have been through the config files in /etc/lightdm and in /usr/share/lightdm but I could not find any big differences before and after update.
I just noticed in Ubuntu 16.04, the 50-unity-greeter does not appear, replaced by a 60-lightdm-gtk-greeter. But in terms of content, they are almost equivalent.
I also noticed some remaining [SeatDefaults] among those files which should be replaced with [Seat:*]. The first one matches the old syntax and some comments appear in the lightdm logs about that.
Other things which may help:
- If I start it up through the "upstart" line in Grub, I get the CLI. I can type sudo lightdm start and it works fine. But a "classic" boot leads to the dead screen.
- When the computer is stucked on that black screen, a CTRL+ALT+F1/2/3/... does not allow to get a console. All I can see is the blinking cursor.
- When it is stuck, a CTRL+ALT+DEL works fine and launches a reset.
So any idea why the updates generate a loss of login screen?