In Linux Mint Nadia (Cinnamon), when I run
sudo apt-get update
I got the following set of error: I removed http://'s due to superuser.com's spam filtering.
Fetched 173 kB in 13s (12.5 kB/s) W: Failed to fetch archive.canonical.com/ubuntu/dists/nadia/partner/source/Sources 404 Not Found [IP: 188.8.131.52 80]
W: Failed to fetch archive.canonical.com/ubuntu/dists/nadia/partner/binary-amd64/Packages 404 Not Found [IP: 184.108.40.206 80]
W: Failed to fetch archive.canonical.com/ubuntu/dists/nadia/partner/binary-i386/Packages 404 Not Found [IP: 220.127.116.11 80]
W: Failed to fetch dl.google.com/linux/deb/dists/stable/Release Unable to find expected entry 'non-free/binary-amd64/Packages' in Release file (Wrong sources.list entry or malformed file)
W: Failed to fetch linux.dropbox.com/ubuntu/dists/nadia/main/binary-amd64/Packages 404 Not Found [IP: 18.104.22.168 80]
W: Failed to fetch linux.dropbox.com/ubuntu/dists/nadia/main/binary-i386/Packages 404 Not Found [IP: 22.214.171.124 80]
E: Some index files failed to download. They have been ignored, or old ones used instead.
The same errors also appear in the Update Manager.