How can I fix a 404 Error using a PPA?
After I installed some updates I restarted my computer.
Some days later I wanted to check for updates because the "update-manager" shows me the following: "The packet information has been updated last 24 days ago." and a window appeared.
That window after downloading packages, said that:
Failed to download the information from the repository
Check your Internet connection
W:GPG error: http://ppa.launchpad.net oneiric Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 5A9A06AEF9CB8DB0, W:Failed to fetch http://ppa.launchpad.net/jsevi83/unity/ubuntu/dists/oneiric/main/source/Sources 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/jsevi83/unity/ubuntu/dists/oneiric/main/binary-i386/Packages 404 Not Found , W:Failed to fetch gzip:/var/lib/apt/lists/partial/ar.archive.ubuntu.com_ubuntu_dists_oneiric_universe_i18n_Translation-en Encountered a section with no Package: header , E:Some index files failed to download. They have been ignored, or old ones used instead.
But my Internet connection works fine.
What do I have to do?