Version:            (using KDE 4.2.0)
OS:                Linux
Installed from:    Ubuntu Packages

I just upgraded my Kubuntu Intrepid (running what I think was KDE 4.1.2) to KDE 4.2, and ended up being unable to log in or do anything else.

I followed the instructions for Kubuntu 8.10 in the release note kubuntu.org: Towards the end of the Adept upgrade process, I was asked to supply a new MySQL root password, and whether I wanted to keep or replace my old kdmrc file (I chose to replace it). After the upgrade was done I tried to log out, but that wouldn't work. I hit ctrl+alt+backspace, and the Alt+E to restart X. From that point on, I couldn't log in to KDE anymore. The login screen would accept my user and pass, but then I'd only get a background image and a mouse cursor and it stayed that way. Reboot didn't help either.

After much weeping and googling, I ran an apt-get upgrade from the command line, which installed kdebase-workspace-data. Then I installed kubuntu-desktop, which also installed kdebase-workspace-bin, after which KDE 4.2 started normally.