The first place I went to for test advice and planning recommendations was http://wiki2.dovecot.org/TestInstallation - The very first test failed. Doc says:
Next check that Dovecot is listening for connections:
# telnet localhost 143 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'.
- OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE STARTTLS AUTH=PLAIN] Dovecot ready.
If you got "connection refused", make sure that Dovecot is configured to serve the imap protocol and listening on the expected interfaces/addresses. The simplest way to do that would be using doveconf(1):
# doveconf protocols listen protocols = imap pop3 lmtp sieve listen = *, ::
If the protocols setting shouldn't contain imap so add it. Also make sure, that relevant !include or !try_include configuration lines are not commented.
*** End doc extract ***
All of the above specified settings are correct. Yet, when I telnet localhost 143, I get:
Trying ::1... # this is certainly suspect Escape character is '^['. Connection closed by foreign host.