broken packages and file permissions and correcness
 

I am a brand-new Ubuntu user. I was trying to install the ability to use restricted formats and executed the following command as per Ubuntu instructions.

sudo apt-get install ubuntu-restricted-extras

It stalled and told me I needed to run dpkg configure - a, which I did.

However, I still cannot update applications, and I get this message when I try:

Failed to check for installed and available applications

This is a major failure of your software management system. Please check for broken packages with synaptic, check the file permissions and correctness of the file '/etc/apt/sources.list' and reload the software information with: 'sudo apt-get update' and 'sudo apt-get install -f'.

The problem is that I do not know how to check for broken packages and do not know how to file permissions and correctness for the file stated.

Would appreciate help.

Try this and see if it works..

sudo aptitude install ubuntu-restricted-extras

If you just installed Ubuntu first try sudo apt-get update.