Updating packages lists
W: The repository 'http://ppa.launchpad.net/albertomilone/hamster-indicator/ubuntu xenial Release' does not have a Release file.
W: Failed to fetch https://cloud.r-project.org/bin/linux/ubuntu/xenial/InRelease  FailReason: ConnectionRefused
W: Failed to fetch https://cloud.r-project.org/dists/trusty-backports/InRelease  FailReason: ConnectionRefused
E: Failed to fetch http://ppa.launchpad.net/albertomilone/hamster-indicator/ubuntu/dists/xenial/main/binary-amd64/Packages  404  Not Found
W: Some index files failed to download. They have been ignored, or old ones used instead.
Warning:  apt-get update failed for some reason