I do see a duplicate in that file. You can remove the whole thing.
1) sudo rm /etc/apt/sources.list.d/prerequists-sources.list 2) sudo rm /var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_precise- updates_main_binary-amd64_Packages 3) sudo apt-get update --- Ubuntu Bug Squad volunteer triager http://wiki.ubuntu.com/BugSquad -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/943638 Title: upgrade lucid to precise has missing candidates To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/943638/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs