My original issue was unrelated to proxy settings. The machines in question were not behind a proxy. The problem here was related to /etc/cron.daily/apt not being marked "executable" after an upgrade --- as far as I know, no one has figured out why this happens, but it is easy enough to resolve manually.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/390319 Title: Ubuntu does not automatically check for updates, even when set to To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/update-notifier/+bug/390319/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
