The upgrade failed to calculate due to the hugin PPA have you enabled. You'll want to install and use the ppa-purge tool to disable and downgrade the packages provided by that PPA, after which the upgrade may be calculated more successfully.
** Changed in: ubuntu-release-upgrader (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/1623563 Title: The upgrade from Ubuntu 14.04 to 16.04 crashes To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1623563/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs