Ran into this when upgrading from 24.04.3 to 26.04.1 on 9/8/2026. I can confirm that I did not remove the file. There's a main.cf.proto in /etc/postfix but no main.cf
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2165958 Title: package postfix 3.10.6-4ubuntu2.1 failed to install/upgrade: old postfix package postinst maintainer script subprocess failed with exit status 1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/postfix/+bug/2165958/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
