After upgrading to Ubuntu 13.04, on the top marging to the left of the language indicator, it appears a red circle with a white line in it, and I cannot open the software updater to solve this problem.
The performance is normal, however from time to time I have to restart my netbook.
Try the following:
Run the following command:
sudo apt-get -f install
Read What exactly does sudo apt-get -f install do?
In the occasional situation where sudo apt-get -f install is not, by itself, sufficient to fix broken packages, see this answer. (This sentence has been shamelessly plagiarised from a comment by Eliah Kagan in the Q&A linked above.)
