Sorry, I misread those lines and confused them with 'precise-updates main'. Uncomment them and save the file again. I actually don't see the duplicate in that source file. Attach the directory:
/etc/apt/sources.list.d --- 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