How can I fix a 404 Error using a PPA?
I am trying to upgrade from 10.10 to 11.04. I have been getting these errors.
Third party sources disabled Some third party entries in your sources.list were disabled. You can re-enable them after the upgrade with the 'software-properties' tool or your package manager.
Error during update A problem occurred during the update. This is usually some sort of network problem, please check your network connection and retry. W:Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/source/Sources.gz 404 Not Found , W:Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/binary-i386/Packages.gz 404 Not Found , E:Some index files failed to download, they have been ignored, or old ones used instead.