Update Manager failed downloads

[ReginaldJ]

Update Manager did it on its own. It failed to download certain things. It showed an error message that I don't understand at all. Would someone kindly tell me what I should do, please?

This is the error message:-
W:GPG error: http://download.opensuse.org ./ Release: The following signatures were invalid: KEYEXPIRED 1332869210, W:Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/source/Sources 404 Not Found
, W:Failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/binary-i386/Packages 404 Not Found
, E:Some index files failed to download. They have been ignored, or old ones used instead.

[zvacet]

Version you run is not supported any more.Best thing you can do is back up all valuable data and do fresh install of 12.10 or maybe 12.04 if you want LTS version.I see you have opensuse repo in your source list.Don´t mix source list because that gives bad results.

[ReginaldJ]

Zvacet, thank you for your reply. It was very useful. My son did a fresh install (it was Linux Mint rather than Ubuntu) and I haven't had any updates to see if it works but, the error messages have disappeared!

Happy New Year.