Trying to upgrade to newest Ubuntu from 12.10. The update manager says
failed to download repository information. Check your internet connection
I checked my internet connection(s), and I'm connected both wired and wireless. So I click on the details of the update manager and get the following text:
W:Failed to fetch http://ppa.launchpad.net/claudiocn/slm/ubuntu/dists/quantal/main/source/Sources 404 Not Found W:Failed to fetch http://ppa.launchpad.net/claudiocn/slm/ubuntu/dists/quantal/main/binary-i386/Packages 404 Not Found E:Some index files failed to download. They have been ignored, or old ones used instead.