ports for SMTP and POP3/IMAP

Operating System & Version
CENTOS 7.8 [server]
cPanel & WHM Version
v88.0.13

cPanelLauren

Product Owner II
Staff member
Nov 14, 2017
13,266
1,304
363
Houston
Well you can't really force the ports, in the sense that if your clients have alternate ports selected they will not be deferred to secure ports. You can enable "Require SSL/TLS to connect" in the exim configuration settings which would require SSL/TLS connection in order for a mail client to connect to the server.
 

cPanelLauren

Product Owner II
Staff member
Nov 14, 2017
13,266
1,304
363
Houston
This is at WHM>>Service Configuration>>Exim Configuration Editor ->
Require clients to connect with SSL or issue the STARTTLS command before they are allowed to authenticate with the server. [?]