Can you remove the file /var/lib/apt/lists/archive.canonical .com_ubuntu_dists_natty_partner_binary-i386_Packages and try again? This might fix the issue for you.
** Changed in: apt (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/840083 Title: update manager To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/840083/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs