The ports you use at this time are ports that belong to mail over a secure connection.
incoming server POP3 |
: |
995 |
incoming server IMAP via SSL/TLS |
: |
993 |
incoming server IMAP via STARTTLS * |
: |
143 |
outgoing server SSL |
: |
465 |
outgoing server STARTTLS |
: |
587 - preferred |
* this is for older mail clients < windows 8 and, for example, older android versions like KitKat and old iOs systems.
The ports associated with a unprotected connection are:
incoming server POP3 |
: |
110 |
outgoing server SSL |
: |
25 of 26 |
It is better to don't use the above ports, rather use the ports that run through a secure connection.