You should use update-manager when you upgrade your system. Or at least use apt-get dist-upgrade, not apt-get upgrade.
See https://help.ubuntu.com/community/FeistyUpgrades
You should use update-manager when you upgrade your system. Or at least use apt-get dist-upgrade, not apt-get upgrade.
See https:/ /help.ubuntu. com/community/ FeistyUpgrades