This error matches a bug that popped up yesterday. For you to recover update-manager and companions, please open a command prompt (gnome-terminal, konsole, or equivalent) and enter:
sudo apt-get update
sudo apt-get dist-upgrade
Basically many of the apt-related utilities are broken, due to a problem in python-apt. See bug # 88104 for details.
This error matches a bug that popped up yesterday. For you to recover update-manager and companions, please open a command prompt (gnome-terminal, konsole, or equivalent) and enter:
sudo apt-get update
sudo apt-get dist-upgrade
Basically many of the apt-related utilities are broken, due to a problem in python-apt. See bug # 88104 for details.