Error during update

A problem occured during the update. This is usually some sort of network problem, please check your network connection and retry.


in the box:

dibuntu.sos-sts.com/repo/dists/feisty/free/binary-i386/Packages.gz 404 Not Found
Failed to fetch http://medibuntu.sos-sts.com/repo/dists/feisty/non-free/binary-i386/Packages.gz 404 Not Found
Failed to fetch http://medibuntu.sos-sts.com/repo/dists/feisty/free/source/Sources.gz 404 Not Found
Failed to fetch http://medibuntu.sos-sts.com/repo/dists/feisty/non-free/source/Sources.gz 404 Not Found