W: Failed to fetch http://ppa.launchpad.net/guido-iodice/compiz-0.8.6-natty/ubuntu/dists/precise/main/source/Sources 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/guido-iodice/compiz-0.8.6-natty/ubuntu/dists/precise/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
Obs: já testei com outro repositório alternativo e acontece o mesmo.
Sugestões? Grato previamente.
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