Comment 2 for bug 866610

Thank you for taking the time to report this issue and help to improve Ubuntu.

The error message in the logs is:

Setting up libpam0g (1.1.3-2ubuntu1) ...
Checking for services that may need to be restarted...Checking init scripts...
WARNING: init script for samba not found.
dpkg: error processing libpam0g (--configure):
 subprocess installed post-installation script returned error exit status 1

Were you shown a prompt during upgrade asking permission to restart pam services on your system?

If you resume the upgrade, does it now succeed?

Please attach the output of this command:
  debconf-show libpam0g