There seems to have been some issue during the upgrade that blocked the creation of the PID file. Manually killing the exim process and re- starting it seems to have fixed the issue.
Apologies for the noise! ** Changed in: exim4 (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1927725 Title: PID file no longer created To manage notifications about this bug go to: https://bugs.launchpad.net/exim/+bug/1927725/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs