System settings stopped showing up

After I have placed my hard drive with Ubuntu 14.04.1 in a new pc system settings won't show up. I have tried:

sudo apt-get install unity-control-center

but I get this

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:
 unity-control-center : Depends: libcheese-gtk23 (>= 3.4.0) but it is not going to be installed
                        Depends: libcheese7 (>= 3.0.1) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

what can I do?

EDIT

The issue may be connected with mesa packages that I had from xorg edgers and I have noticed that

• unity-control-center depends on libcheese7
• libcheese7 depends on gstreamer1.0-clutter
• gstreamer1.0-clutter depends on libcogl15
• libcogl15 depends on libegl1-mesa-drivers
• libegl1-mesa-drivers depends on libegl1-mesa-drivers
• libegl1-mesa-drivers depends on libglapi-mesa ( = 10.1.3-0ubuntu0.3 )

and I have installed :

libglapi-mesa 10.5.0~git20150105.21a280f8-0ubuntu0ricotz~trusty from xorg-edgers PPA.

I have tried installing it with:

sudo apt-get install libglapi-mesa=10.1.3-0ubuntu0.3
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:
 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
 libcheese7 : Depends: libclutter-gst-2.0-0 (>= 0.10.0) but it is not going to be installed
              Depends: gstreamer1.0-clutter but it is not going to be installed
 libclutter-gtk-1.0-0 : Depends: libclutter-1.0-0 (>= 1.13.10) but it is not going to be installed
                        Depends: libcogl15 (>= 1.15.8) but it is not going to be installed
 libcogl-pango15 : Depends: libcogl15 (>= 1.15.8) but it is not going to be installed
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.

I have that PPA already disabled with

sudo ppa-purge  ppa:xorg-edgers/ppa && sudo apt-get update

So the problem has been with the dependencies, namely

libegl1-mesa-drivers depending on libglapi-mesa ( = 10.1.3-0ubuntu0.3 ) (maybe should be >=)

I have added the xorg-edgers PPA again and then properly downgraded with ppa-purge as so:

sudo add-apt-repository ppa:xorg-edgers/ppa && sudo apt-get update
sudo ppa-purge  ppa:xorg-edgers/ppa && sudo apt-get update

and now I have all packages from xorg-edgers removed and system settings dialog opens up :)

There is a bug report for this here. (The solution came from the #10 reply)

And apparently my issue was solved by entering the following line:

sudo apt-get install libglew-dev libcheese7 libcheese-gtk23 libclutter-gst-2.0-0 libcogl15 libclutter-gtk-1.0-0 libclutter-1.0-0

Try doing sudo apt-get install -f unity-control-center or search for the missing package names and install them manually.