Hi! You're trying to run a package that is not an official Ubuntu package but it belongs to a PPA. https://launchpad.net/~markus-tisoft/+archive/rt3090/+packages
Unfortunately the package hasn't been updated for later versions of Ubuntu so this is why the package isn't found. I convert this bugreport to a question so it'll stand a greater chance of being noticed and answered. Good luck! ** Changed in: update-manager (Ubuntu) Status: New => Invalid ** Converted to question: https://answers.launchpad.net/ubuntu/+source/update-manager/+question/223021 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1074163 Title: W:Failed to fetch http://ppa.launchpad.net/markus- tisoft/rt3090/ubuntu/dists/precise/main/binary-amd64/Packages 404 Not Found , E:Some index files failed to download. They have been ignored, or old ones used instead. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/1074163/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs