No Login screen - only black, after update today

[amigabill]

I updated 17.10 today, and cannot login anymore to a GUI. I get the Kubuntu small screen in Virtualbox, with the 4 blue dots showing some boot progress, which changes size within the Virtualbox screen a few times, then Kubuntu goes full-screen black. No GUI login prompts.

I can do ctrl-alt-f1 to a text screen and login there, do a startx or xstart (I forget now), and then I will get my old Konsole window up on an all-black background, I can open muon from that Konsole commandline, and open other GUI apps from commandline.

If I shut down, then I see the Kubuntu logo screen whille things turn off.

So it seems like Plasma is the missing/broken piece.

I was able to see a small message window that says
Plasma Failed to Start - Plasma <2>
Plasma is unable to start as it could not correctly use OpenGL 2.
Please check that you graphic drivers are set up correctly.

So, I have Virtualbox drivers 5.2.6 version installed, and worked fine as I did apt-get update and upgrade commands in Konsole. After Kubuntu update was complete, the login screen and plasma desktop are dead and just a void of darkness. I have reinstalled vbox driver kit without any error messsages.

Any ideas, as yet another Kubuntu update has destroyed itself here...

[larbac]

Same problem here, after updating to last KDE version.
My fortune is that Firefox opens automatically after boot...
How to solve this?

[GreyGeek]

It may be that the upgrade didn’t complete properly. In a konsole issue:
sudo apt -f install
Followed by:
sudo dpkg —configure -a

Repeat until both do nothing.

[jlittle]

Same problem here, after updating to last KDE version.
My fortune is that Firefox opens automatically after boot...
How to solve this?

Assuming you're not getting a black screen like the OP, it seems like you're restoring an old "session". You could try System Settings -> Desktop Session, click On Login, Start with an empty session.