$ apt-get install -f -o 'Dpkg::Options::=--force-confmiss --force-all --force-confnew --overwrite-conffiles' --reinstall at-spi2-core
Reading package lists... Done
Building dependency tree       
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 kde-workspace-bin : Depends: qdbus but it is not going to be installed
 libqt4-dbus : Depends: qdbus (= 4:4.8.5+git192-g085f851+dfsg-2ubuntu4) but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

I don't quite understand "but it is not going to be installed". Why doesn't it install it then?

apt-get -f install does not help, it does nothing:

$ apt-get install -f
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
  • You could try to find out why qdbus is not being installed by installing it yourself: sudo apt-get install qdbus. – Jos Dec 22 '14 at 11:15
  • 5
    @Jos: I did that. Now it works. However, that doesn't really answer my question or what the problem was. – Albert Dec 22 '14 at 11:15
  • I suppose it was the combination of options in your original apt-get command that prevented apt from installing additional dependencies. – Jos Dec 22 '14 at 11:20
  • Here it was that I missed main and only had deb http://de.archive.ubuntu.com/ubuntu/ wily universe multiverse in addition to trusty. Then, apt wanted to install a package from universe, which depended on versions available in wily/main only and thus could not be installed. – koppor Jan 23 '16 at 14:45
  • 1
    Try adding the missing package to the install command: sudo apt-get install --reinstall at-spi2-core qdbus libqt4-dbus – antivirtel Apr 2 '16 at 20:58

This worked for me.

$ sudo apt-get install <missing-package-1> <missing-package-2> ...

I don't know why this is necessary, but manually installing the problematic packages worked.

After installing the first round of unmet dependencies, another one popped up, but I repeated the process and it sorted itself out after two cycles.

  • 14
    Wow, it really is this simple... It makes me wonder why it wouldn't install in the first place? – Jacksonkr Apr 19 '16 at 3:47
  • This helped me too, but had to run twice second time with reverse order of package names. Not sure if reversing order was necessary. – PeterM Apr 22 '18 at 16:17

As this question also didn't help, I found on this LinuxQuestions thread a hint that helped me:

Do you have a mixed /etc/apt/sources.list? It appears that you're trying to install one package from a newer repository but that it doesn't have access to a repository with the newer dependencies.

  • A mixed sources file, or maybe one with only a single repository but that has missing packages – golimar Mar 14 '18 at 13:22
  • I had the same problem - my sources.list had only the main repository and the dependency was somewhere else (universe, restricted, ...). The error message is very misleading. – WoJ Sep 20 '18 at 9:00
  • Yes, this is a possible reason. For example, ubuntu 20.04 with ubuntu 16.04 (xenial)'s sources.list, would make apt install xxx report similar problem. – HaxtraZ Nov 11 '20 at 10:49

I ran into this issue and solved it by running:

sudo apt-get update
sudo apt-get upgrade

Then when I ran the original "apt-get install" command succeeded.


I also had the same issue while installing Guake; it showed unmet dependencies with Python. Even trying to reinstall python using sudo apt-get install --reinstall python did nothing.


Step-1: I had to remove and install python again using:

Note: Uninstalling python leads to removing many other dependencies which may break the installed Ubuntu, so be careful while uninstalling python

sudo apt-get purge python

sudo apt-get install python

Step-2: Install the original package (in my case it was guake)

sudo apt-get install guake

This installed all necessary dependencies.

Try the same procedure w/ your packages and it should work for you too.

  • 2
    Removing Python, even only temporarily, is a bad idea as it will likely remove lots of depending packages with it and it is needed to run many important system commands. – Byte Commander Sep 14 '17 at 20:03
  • I was aware of this possibility but i wasn't able to solve my issue otherwise....searched a lot but could not find a working way....as of now my ubuntu has not broken ..... waiting for it in future ;) ... – imflash217 Sep 14 '17 at 20:48

I had similar problems with cups-filters on raspberrypi caused by realvnc-vnc-server. It was due to foomatic-filters being deprecated. I couldn't install or uninstall anything so what worked for me was to delete the apt cache for cups-filters.

sudo rm /var/cache/apt/archives/cups-filters*

Then the install worked as suggested by @funroll

sudo apt install cups cup-filters


Nothing above worked for me but following procedure saved me

sudo dpkg --configure -a 

this will list the broken packages and

sudo dpkg -r librrd4 

{librrd4 and libpng12 were my broken pakages solved the problem

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.