I tried to help a friend with hard drive boot problems.
I first asked her to make a rescue disk (Ubuntu 12.04.3), and boot from it.
Then I asked her to open a console (Alt+F1) and use
sudo to become root. All OK.
Then I told her to install
openssh-server - so I can remotely login and look at the system - but that does not work: openssh-client (and some other applications) are reported as "not going to be installed".
But openssh-client is already installed: checking with
dpkg -l openssh-client shows this to be the case.
Why doesn't this work?