How to set up mail on the server?

Question

Mail server

Good day.
The situation is as follows, 2 domains had mail for them on the hosting, it was necessary to transfer the mail to a server within the company, the sites stand and work on it (on the same domains, but the mail was on the hosting). The server has a local ip 192.168.0.* and forwarded ports and the site goes down, as there is a static ip.
Transfer: letters were moved to already created mailboxes in the ISP manager and the MX records for the domain and the mail record in the DNS were replaced.
Here is a screen of ports on the modem: ssmaker.ru/c8b5d49b
Letters do not leave and do not come. What can be wrong?)

Answer 1

go to the logs and find out the reason