Here's a debdiff[1] that I have tested and mitigate the situation with the reproducer using VirtualBox.
The proposal patch integrate a custom "debian/cups-daemon.prerm" maintainer script in case the pre-removal "old-version" from the installed package fails (as seen using the above reproducer) and then switch to the pre-removal script from the "new version" from the package to-be install in order to stop cups.socket and cups.path indivually before #DEBHELPER#. [1] debdiff: lp1642966_xenial.debdiff - Eric ** Patch added: "lp1642966_xenial.debdiff" https://bugs.launchpad.net/ubuntu/+source/cups/+bug/1642966/+attachment/4934958/+files/lp1642966_xenial.debdiff ** Changed in: cups (Ubuntu Xenial) Status: Triaged => In Progress ** Changed in: cups (Ubuntu Xenial) Assignee: (unassigned) => Eric Desrochers (slashd) ** Tags removed: verification-done-xenial ** Tags added: regression-proposed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1642966 Title: package cups-daemon 2.1.3-4 failed to install/upgrade: subprocess new pre-removal script returned error exit status 1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cups/+bug/1642966/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
