After i type sudo apt-get update ubuntu shows the following error.
W: Failed to fetch http://archive.canonical.com/dists/freya/partner/binary-amd64/Packages 404 Not Found [IP: 91.189.92.150 80] W: Failed to fetch http://linux.dropbox.com/ubuntu/dists/freya/main/binary-i386/Packages 404 Not Found [IP: 108.160.172.206 80]