Hello Kaylee and thanks for filing this bug report. From the attached logs I see that updating mailman failed because:
OSError: [Errno 2] No such file or directory: '/var/lib/mailman/qfiles/out/1645451769.107923+c16c9118034896266b63a04bfa1653d5c627b208.bak' Perhaps that backup file has been manually removed at some point? Since it seems likely to me that this is a local problem, rather than a bug in Ubuntu, I'm marking this bug as Incomplete. If you believe that this is really a bug, we'd be grateful if you would then provide a more complete description of the problem, explain why you believe this is a bug in Ubuntu rather than a problem specific to your system, and then change the bug status back to New. (Side note: keep in mind that Focal is the latest Ubuntu release shipping mailman2.) ** Changed in: mailman (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/1961870 Title: package mailman 1:2.1.29-1ubuntu3.1 failed to install/upgrade: installed mailman package post-installation script subprocess returned error exit status 1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mailman/+bug/1961870/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs