While upgrading to 14.04 using
sudo do-release-upgrade my network connection was interrupted and several packages failed to upgrade.
do-release-upgrade again reported
No new releases found but
apt-get listed many packages "kept back", so it seemed the system was in an intermediate state. I ran
apt-get dist-upgrade which installed those packages again, then
apt-get autoremove after which apt seemed happy.
However, after restarting I cannot log in at the GUI prompt. After entering my password the error "Failed to start session" appears in red. I am still able to log in from the command prompt, but I don't know what to do to solve or debug the GUI log in failure.
After issuing the following command I was able to log in again:
I had previously removed
update-notifierwhich caused some other packages to be removed, some of which it seems were necessary to successfully perform the distribution upgrade.