PROBLEM
I want to enable SMTPS on port 587.

ENVIRONMENT

• On-Premise Server + WebMail Installations: Version 6.0 > Current Version

CAUSE
Exim (and most SMTP servers) only start TLS, or SSL connections after being prompted with the STARTTLS command. There is an older implementation that presents SSL on connection however, and this can be enabled via Atmail.

RESOLUTION

1. Open up /usr/local/atmail/mailserver/configure.
2. Add these lines at the top:
   

   tls_on_connect_ports = 465:587
   daemon_smtp_ports = 25:465:587

3. Then add your SSL definitions below (if you have not defined the following already):
   

   tls_advertise_hosts = *
   log_selector = +tls_peerdn
   tls_certificate=/usr/local/atmail/mailserver/server.crt
   tls_privatekey=/usr/local/atmail/mailserver/server.key

   Where server.crt and server.key are your SSL files.
4. Restart Atmail
   

   % /etc/init.d/atmailserver restart