Possible Duplicate:
How can I fix a 404 Error using a PPA?
I got error in update-manager
W:Failed to fetch http://archive.canonical.com/commercial-ppa-uploaders/skype/ubuntu/dists/quantal/main/binary-i386/Packages 404 Not Found [IP: 91.189.92.150 80] , E:Some index files failed to download. They have been ignored, or old ones used instead.
How do I resolve it?