I had Dovecot running very well on Ubuntu 14.04. Then I decided that since That version of Ubuntu was now out of support, I would build a new server on 18.04, which has been done.

I thought I could take the old dovecot.conf and everything in conf.d that had been customized and drop it in place, and everything would just work. That has proven not to be correct. The files that had been edited were the main /etc/dovecot/dovecot.conf, and in conf.d, 10-master.conf, 10-ssl.conf, and 10-mail.conf. I have restored the original package-supplied versions of these files and restarted Dovecot, but still no one can connect. Here's my configuration, with the version number at the top:

# 2.2.33.2 (d6601f4ec): /etc/dovecot/dovecot.conf # Pigeonhole version 0.4.21 (92477967) # OS: Linux 4.15.0-64-generic x86_64 Ubuntu 18.04.3 LTS auth_debug = yes auth_debug_passwords = yes mail_debug = yes mail_location = mbox:~/mail:INBOX=/var/mail/%u mail_privileged_group = mail namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { driver = pam } protocols = " imap lmtp" userdb { driver = passwd } verbose_ssl = yes

The edits that were made to the aforementioned files were not actually done by me, so I can't explain why certain choices were made, except for obvious ones such as SSL key paths. But I figured the system should work at least on a vanilla configuration.

Postfix is also involved in this, so the problems may not at all be with Dovecot, but with Postfix. I think I just need to draw the line between them and be able to know definitely that at least one half of the system is functioning correctly so I know I can mark that part as working, and proceed with debugging the other. My bet at this point is that it's not a Dovecot problem, but I'm not clear on how to determine this, with or without my changed files.

Thanks in advance.