==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version: 1.4.0 MARIADB edition.
- Deployed with: downloadable installer
- Linux/BSD distribution name and version: Ubuntu 20.04
- Database: MariaDB (MySQL)
- Web server (Apache or Nginx): Nginx
- iRedAdmin-Pro? - NO
- mail.log has no related info - no other logs found
====

Hello iRedMail forum!

I have a domain which a client wants to use in their Gmail interface, as an alias.
So within gmail they can send / receive as their custom domain I have set up.

In Gmail, when trying to add any of my various domains and email accounts, get a "Couldn't reach server. Please double-check the server and port number." I've tried 587/TLS, 587/SSL, 465/TLS, 465/SSL, 25/TLS. I can connect using STARTTLS 587 just fine in my mail client (Thunderbird).

I've tried multiple domains, none work as gmail alias.
I have no problem connecting 587 via Mail Client or other connections (Wordpress).

I searched the forums here using site:forum.iredmail.org and found this:
https://forum.iredmail.org/topic9761-se … count.html
...but seems they are trying to alias the otherway (from gmail into iredmail).
Instead of using Gmail frontend with the iredmail alias.

I have been running a successful iRedmail for a couple of months now. No problems sending or receiving, or connecting from Thunderbird mail client nor some Wordpress instances. I have configured Let'sEncrypt and correctly configured the bundled certs there.

Nothing in mail.log regarding connection attempts. Not sure what other logs to check if any.

SPF, DKIM, DMARC all setup and I play nicely with various postmaster portals (Google, Outlook) so no mail delivery problems in general.

If anyone has any ideas, leads, thoughts, I would appreciate it!
I would be happy to buy a coffee (tip) for anyone who helps lead to resolution.

Thanks!