Comment 3 for bug 223864

From Gusty 7.10 (all upgrade installed) to Hardy 8.04 AMD 800mhz i386

had no action after it got to checking database. Detail switch ghosted. Switched to command line

    sudo aptitude install update-manager-core
    sudo do-release-upgrade
    .....
    Calculating the changes

    Could not calculate the upgrade

    A unresolvable problem occurred while calculating the upgrade.

    This can be caused by:
    * Upgrading to a pre-release version of Ubuntu
    * Running the current pre-release version of Ubuntu
    * Unofficial software packages not provided by Ubuntu

    If none of this applies, then please report this bug against the
    'update-manager' package and include the files in
    /var/log/dist-upgrade/ in the bugreport.

    Restoring original system state

    Aborting
    Reading package lists: Donem gutsy-backports/universe Packages: 95
    Reading state information: Done
    Reading state information: Done
    Reading state information: Done