It first happend about a week ago that I received this error message the first time. It shows up daily.
W:Failed to fetch http://de.archive.ubuntu.com/ubuntu/dists/natty/multiverse/source/Sources 404 Not Found [IP: 184.108.40.206 80] , E:Some index files failed to download. They have been ignored, or old ones used instead.
I can do updates from other ppa as usual. I noticed that problem in relation to special ppa defined by the user, but I can't imagine that natty's multiverse could be down for days.
Is there something I can check on my system to solve this?