Comment 4 for bug 992335

Thanks for taking the time to report this bug in Ubuntu.

For some reason the backuppc process has either not terminated or has terminated uncleanly leaving a pid file lying around which is blocking this upgrade.

I was not able to replicate this either during upgrade from 11.10 to 12.04 or by re-installing on 12.04.

Please can you check to see if PID 1237 is actually running:

   ps -aef | grep 1237

If it is then:

   sudo service backuppc stop

if it is not then:

  sudo rm -f /var/run/backuppc/BackupPC.pid

and then run the following to complete your install:

  sudo apt-get -f install

I'm marking this but as 'Incomplete' - please can you update this bug report if the above resolves your issue and mark the bug as 'Invalid' .

Thanks