> First you need to disable any ssl_listen in the protocol section: > > protocol imap { > listen = *:143 > # ssl_listen = *:993 > } > protocol pop3 { > listen = *:110 > # ssl_listen = *:995 > } > > Then set: > disable_plaintext_auth = yes > > That will give you the ability for users to only log in via TLS.
This will work for plain text authentication. However, we are (partly) using GSSAPI, which is not a plain text authentication mechanism. TLS (through STARTTLS) won't be enforced in these connections. Durk