Working from 12.10, I've tried upgrading to 13.04 from the command line and from the Ubuntu Software Updater.
From the command line I entered sudo apt-get update && sudo apt-get dist-upgrade. After it completed I typed sudo update-manager -d. The latter of course just opens the Ubuntu Software Updater, which I could just as easily do from Dash, which I also did.
Nonetheless, after the updater looked up the updates, I get the following message:Failed to download repository informationIn the details it says:
Check your Internet connection.
W:Failed to fetch http://ppa.launchpad.net/cooperjona/...-i386/Packages 404 Not Found
, E:Some index files failed to download. They have been ignored, or old ones used instead.
Is there something more I need to download and install. I've never had this issue upgrading before?