Not connect to mail from i-mac devices

[Wonder]

Well, this strange case happens to me, from any other client, such as thunderbird, everything is perfect but... from two new i-mac devices, it does not connect to mail, testing, I have seen that, if I deactivate Firewall then it does connect, if I activate firewall does not connect.
But the imap firewall ports are correctly open, 993, 465...etc...otherwise it wouldn't work from Thunderbird for example.
And I don't like having to have the firewall disabled.

Any ideas? Because for me, it's the strangest thing I've ever seen...

Regards.

[Wonder]

Any iddea or suggestion?

Regards!

[overseer]

Are you supporting STARTTLS ports in addition to the SSL/TLS mail ports?
143 for IMAP, 25 for SMTP, 110 for POP3, 587 for submission.
I can't say how your Mac clients are set to connect to the server, but they can support both STARTTLS or SSL/TLS.

[Wonder]

Are you supporting STARTTLS ports in addition to the SSL/TLS mail ports?
143 for IMAP, 25 for SMTP, 110 for POP3, 587 for submission.
I can't say how your Mac clients are set to connect to the server, but they can support both STARTTLS or SSL/TLS.

First of all, thanks for answering and apologies for the delay in answering, I spent a few days without being able to answer and the email notification entered my spam folder...

Indeed, in firewall I have those ports open, this is a list of the ports (I have removed those that are not relevant and/or are used for other things):

tcp
IN: 20, 21, 25, 53, 80, 110, 143, 443, 465, 587, 993, 995,
OUT: 20, 21, 25, 53, 80, 110, 113, 443, 143, 993, 995,

I'm seeing, 465 and 587 are not in OUT but they must be in IN not OUT (correct me if I'm wrong).

What I commented, thanks for the answer and sorry for my delay in answering, between the fact that I could not connect for a few days and the email notification arrived at spam...

This is a topic that has me intrigued, indeed, a Mac connects just like any other (I think...)