Обнаружил сегодня схожую проблему. И переустанавливал и папки с настройками удалял всё без толку.
После попытки сделать всё по совету bukass`a выдаёт следующее:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:
The following packages have unmet dependencies:
account-plugin-google : Depends: libaccount-plugin-google but it is not going to be installed or
ubuntu-system-settings-online-accounts but it is not going to be installed
indicator-bluetooth : Depends: unity-control-center but it is not going to be installed or
gnome-control-center but it is not going to be installed or
ubuntu-system-settings but it is not going to be installed
indicator-network : Depends: unity8 (>= 7.82) but it is not going to be installed
libqt5feedback5 : Depends: libqt5multimedia5 (>= 5.0.2) but it is not going to be installed
libqt5quick5 : Depends: libqt5gui5 (>= 5.2.0) but it is not going to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
Не понимаю, почему так произошло и что делать дальше. Подскажите пожалуйста.
Ubuntu 14.04
UPD
Переустановил только ядро. Всё заработало. Салютую, спасибо. Обновляться dist-upgrade`ом больше не буду.