Thanks very much. I did apt-get update and it seemed to go fine (though no updates to install - I updated via a broadband connection on the weekend).
Do I have to run the export command each time I try to update? When I closed teh terminal, reopened it and then tried 'sudo apt-get update', I got failed to fetch messages again. Synaptic doesn't seem to work either. When I try to reload the repositories, I get the message below. I have set the manual proxy settings in teh preferences menu correctly, I think. Any ideas? I really appreciate your help. Could not download all repository indexes The repository might be no longer available or could not be contacted because of network problems. If available an older version of the failed index will be used. Otherwise the repository will be ignored. Check your network connection and the correct writing of the repository address in the preferences. -- network in unreachable with netmask 255.255.255.255 https://launchpad.net/bugs/50591 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs