I am running Ubuntu 12.04 (Precise Pangolin). I made the mistake of adding as a source the gnome3-staging PPA intended for Vivid Vervet, and this has caused some problems when I upgrade.
Although I have already removed this PPA from the sources list, the problem persists, so that there is always an error for 'unmet dependencies'. How can I solve this situation? Also, I want to remove from my system those Vivid Vervet packages which I had installed. Thank you
First you should remove the added repository. use ppa-purge Difference between "ppa-purge" and "add-apt-repository -r"?
ppa-purge - Disables a PPA and reverts to the official packages if applicable. For example, if I added the xorg-edgers PPA and installed the Nvidia drivers, if I do a ppa-purge on said PPA, it would not only disable the xorg-edgers PPA but also revert the NVIDIA drivers from the one in the PPA to the official ones found on the official Ubuntu repositories.
Now after purging the added repository then update software list
sudo apt-get update
then do upgrade
sudo apt-get dist-upgrade
But you have to notice that you may still need to downgrade some packages manually. To downgrade a package you can use the command:
sudo apt-get install pkg_name=version
