I used kubuntu ppa to install kubuntu-desktop on Ubuntu unity 16.04, the canonical one. It led to broken packages. As others have pointed out here and here, they figured out how to install kubuntu-deskop anyway however, I am not inclined to use plasma anymore. So I am uninstalling it. I just unchecked the kubuntu ppa/backports/Ubuntu Xenial in Softwares & Updates > Other Software. And then sudo apt-get remove kubuntu-desktop. I later realized that this was not the best way to rid my system of the kubuntu system conflicting with my unity DE. Anyway I learnt this the hard way when I was trying to install unity tweak tools.
So basically I realized that I had not gotten rid of softwares installed by the ppa in a good way leading to broken packages. Now I do not notice this when installing other packages. Only when dealing with qt, unity etc. I face this issue. I tried installing all unity stuff hoping this will remove all the kubuntu related packages.
sudo apt-get install unity-*
I got this error:-
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:
unity-chromium-extension : Depends: webbrowser-app
unity-scope-click : Depends: account-plugin-ubuntuone
Depends: pay-service but it is not going to be installed
Depends: ubuntu-sdk-libs but it is not going to be installed
unity-scope-click-autopilot : Depends: ubuntu-ui-toolkit-autopilot but it is not going to be installed
Depends: unity8-autopilot but it is not going to be installed
unity-scope-home : Conflicts: unity-scope-deviantart
Conflicts: unity-scope-gallica
Conflicts: unity-scope-github
Conflicts: unity-scope-googlenews
Conflicts: unity-scope-openweathermap
Conflicts: unity-scope-soundcloud
Conflicts: unity-scope-yahoostock
unity-scope-tool : Depends: unity8-common (= 8.12+16.04.20160401-0ubuntu1) but it is not going to be installed
unity-webapps-qml : Depends: qtdeclarative5-ubuntu-ui-toolkit-plugin or
qtdeclarative5-ubuntu-ui-toolkit-plugin-gles but it is not going to be installed
unity-webapps-service : Depends: webapp-container
unity8-private : Depends: pay-service but it is not going to be installed
Depends: qtdeclarative5-gsettings1.0 but it is not going to be installed
Depends: qtbase-abi-5-5-1
Depends: qtdeclarative-abi-5-5-0
E: Unable to correct problems, you have held broken packages.
Elsewhere they advise to clean, auto-clean, upgrade,dist-upgrade,auto-remove etc. Tried all, but no result. Unity seems to be in conflict. interestingly when I try :-
sudo apt-get install python3-pyqt5
It runs into error:-
The following information may help to resolve the situation:
The following packages have unmet dependencies:
python3-pyqt5 : Depends: qtbase-abi-5-5-1
E: Unable to correct problems, you have held broken packages.
Using aptitude also is futile. It just says i cannot resolve your problem and does nothing. Can someone help me figure out how to remove kubuntu and the other softwares properly and reinstall unity properly.
sudo apt install -f? It's a general catch all for the 'broken packages' error – brndn2k Apr 28 '17 at 03:52