==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
iRM 0.9.8 - iRedMail version (check /etc/iredmail-release):
Ubuntu 18.04 x64- Linux/BSD distribution name and version:
MySQL - Store mail accounts in which backend (LDAP/MySQL/PGSQL):
Nginx - Web server (Apache or Nginx):
no - Manage mail accounts with iRedAdmin-Pro?
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====
please refer to: https://serverfault.com/questions/94387 … nal-server

in a nutshell, I cannot send mail from internal server to mail accounts on the iRM server - access denied or connection timed out
Zhang?

I will buy you a pound of coffee!