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My update manager doesn't work and comes up with this:
please check your internet connection W:Failed to fetch http://ppa.launchpad.net/ferramroberto/java/ubuntu/dists/quantal/main/source/Sources 404 Not Found W:Failed to fetch http://ppa.launchpad.net/ferramroberto/java/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.
but my internet connection is fine please help.