When I was given the option to Upgrade to Ubuntu 12.10 I did try to Upgrade, but while it was upgrading the internet connection was lost and the system went through a partial upgrade. Now when I try to open the Update Manager or the Software Sources it opens and crashes automatically.
What should I do?
When package upgrades are interrupted in midway, normally doing sudo dpkg --configure -a && sudo apt-get -f install && sudo apt-get upgrade will save the situation, but when is a full release upgrade (jumping from a version to another) the steps becomes more tricky.
What's the best solution for this cases? Reinstall. If you are not capable to reinstall, you may want to continue the upgrade using sudo update-manager-text or sudo apt-get dist-upgrade (the last one you shall modify your sources.list from oneiric to precise, see my command at the end), but that I won't guarantee will work. Other option is sudo do-releases-upgrade, but you must make sure that the process is not interrupted this time around.
To use apt-get dist-upgrade
sudo sed s/oneiric/precise/g /etc/apt/sources.list
sudo apt-get update
sudo apt-get dist-upgrade
Experienced a similar problem with my old laptop. I tried most of the suggestions above but kept coming with the same "partial upgrade" problem which when you run it fails giving other permissions/upgrade errors.
After many attempts I decided to give synaptic package manager a try. I chose the option for custom filters - then the option for "marked changes" and found one linux header marked as upgradable. Immediately upgraded the package which went smoothly. Then reloaded synaptic again and went down the same options in custom filters - this time I chose the option "upgradable(upstream). Found more packages that had failed in the upgrade and upgraded those. Reloaded synaptic once more and this time around synaptic found fewer packages that needed upgrading. After upgrading the last few packages I rebooted and everything went on smooth from there. Hope this helps someone.
