For recieving e-mails from the Internet ONLY Port 25 is relevant.E-Mail between Servers on the Internet is always sent to the recipients Port 25.
Ports 465 (SSL) and 587 (Submission) are ONLY used by clients sending mails. NethServer can handle clients mail (With Authentification) also on Port 25 (Using TLS).
What could be possible, is that your provider is now (not earlier) blocking Port 25. A lot of providers globally do this for consumer / residential Internet connections.
These provider people, by their thinking, a consumer will NEVER have a full blown mail server at home… So they block incoming and sometimes also outgoing port 25, to reduce spam.
You can check this, if you can test from your mobile (With 4G) as hotspot to your Notebook.
Use a command window, and use:
telnet my-home-servers-IP 25
This command will work for ANY mailserver. The server will answer with it’s version and capabilities, depending on the software running mail.
If this works, then you know it’s NOT your provider blocking you!
Note: I can also do the test for you - the Internet IS global! Or anyone else, a friend or someone you know. You’ld just need to pass your momentary external IP to test. (PM)
My 2 cents