Could not download all repository indexes

[trivas7]

Output from update manager:

<quote>Failed to fetch http://dl.google.com/linux/chrome/deb/di.../InRelease  Failed to fetch http://dl.google.com/linux/talkplugin/de.../InRelease  Failed to fetch http://archive.ubuntu.com/ubuntu/dists/xenial/InRelease  Failed to fetch http://archive.ubuntu.com/ubuntu/dists/x.../InRelease  Failed to fetch http://security.ubuntu.com/ubuntu/dists/.../InRelease  Failed to fetch http://archive.canonical.com/ubuntu/dist.../InRelease  Some index files failed to download. They have been ignored, or old ones used instead.</quote>

Thanks for any help!