==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): 4.3
- Deployed with iRedMail Easy or the downloadable installer? easy
- Linux/BSD distribution name and version: Ubuntu
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): mysql
- Web server (Apache or Nginx): ngnix
- Manage mail accounts with iRedAdmin-Pro? yes
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

I got this strange problem with microsoft office outlook.
When i add 1 new account to it ... it does not work automaticly
But if I use other mail client like eM Client there i don't have any problems.

When i compare the settings from eM Client for SMTP and IMAP there equal.

The only problem i get is that there is something is wrong.

What is the reason ? Does outlook works different ?

What dns records needs to be there for Office to perform it automatic adding account ?

In Microsoft STARTTLS selected -> then it works. (port 587 and 143)