i get an error when i update my ubuntu 14.10
this is an error :
Err http://ppa.launchpad.net utopic/main amd64 Packages
404 Not Found
Err http://ppa.launchpad.net utopic/main i386 Packages
404 Not Found
Ign http://kambing.ui.ac.id trusty/universe Translation-en_US
Fetched 22,6 MB in 4min 12s (89,5 kB/s)
W: Failed to fetch http://ppa.launchpad.net/tualatrix/ppa/ubuntu/dists/utopic/main/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/tualatrix/ppa/ubuntu/dists/utopic/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
what should i do fix that error ?