Unable to repair packages in Ubuntu Software Center

Solution 1:

Open a terminal and use these commands

sudo apt-get install -f

sudo dpkg --configure -a

sudo apt-get update && sudo apt-get upgrade

After the last one you should be able to open your USC again without faults.

Edit

Comments explain that key 5A9A06AEF9CB8DB0 is missing, during sudo apt-get update this fault comes up:

W: GPG error: http://ppa.launchpad.net oneiric Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 5A9A06AEF9CB8DB0

To repair the key these commands can be used:

sudo gpg --keyserver keyserver.ubuntu.com --recv-keys 5A9A06AEF9CB8DB0
sudo gpg --export --armor 5A9A06AEF9CB8DB0 | sudo apt-key add -

After that sudo apt-get update should work, if you get no faults on it you can open USC again and click on the repair button.