I had to reinstall kde plasma desktop, and somehow at the end, got this error:
could not perform immediate configuration on phonon-backend-vlc. It referred to a man page that was less than useful.
At the end it seemed that it was some kind of “protection” which is triggered on huge installs.
So I figured out that I had to install the offending package by itself. I located the package in the cache and did this:
dpkg -i /var/cache/apt/archives/phonon-backend-vlc_0.6.0-1_i386.deb
Upon which it spurted out dependency issues. So:
apt-get -f install phonon-backend-vlc
which seemed to work.
Then I continued the failed installation:
apt-get -y install kde-plasma-desktop