Sorry if this has already been answered but here is the error i am getting..

W:Failed to fetch http://repository.spotify.com/dists/...source/Sources 404 Not Found
, W:Failed to fetch http://repository.spotify.com/dists/...-i386/Packages 404 Not Found
, W:Failed to fetch http://ppa.launchpad.net/pmcenery/pp...source/Sources 404 Not Found
, W:Failed to fetch http://ppa.launchpad.net/pmcenery/pp...-i386/Packages 404 Not Found
, E:Some index files failed to download. They have been ignored, or old ones used instead.

If anyone could help me it would be greatly appreciated.