Ubuntu - problem s paketom

Poskušam namestiti en program (sudo apt-get install), vendar mi izpiše tole:

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:
kolourpaint4 : Depends: kde-runtime but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Kako se rešim te napake, da bom program lahko namestil?

sudo apt-get install kde-runtime

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:
kde-runtime : Depends: kdelibs5-plugins (>= 4:4.13.0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Če napišem "sudo apt-get install kdelibs5-plugins", mi spet javi neko drugo napako. Tako se vrtim v začaranem krogu.

Tudi to javi podobno napako. Škoda živcev, pa tudi časa za ugibanje nimam. Bom verjetno jutri formatiral in si prihranil čas.

Tudi to ne dela. Pregledal sem že vsako stran, ki jo Google najde. Več nimam kaj iskat. Nekje je prišlo do napake in sedaj večino programov ne morem instalirat, tako da s takim sistemom nimam kaj delat.