Hello everyone.

We have the following problem:

Odoo v17 on premise (Linux Ubuntu 22.04 LTS)

Postfix on the same server

Exchange Online (EXO)

Mass mailing (newsletter 2500+ recipients)

Exchange Online is limited to 50 emails/min

Odoo sends with a direct connection to EXO

Too many emails per minute.

That's why EXO blocks, due to suspicion of SPAM,

the mailbox.

The Postfix was therefore subsequently added to the Odoo server

installed.

The Postfix config should be correct.

When I send an email via the command line

It will also arrive where I sent it.

If I use Postfix in Odoo as an outgoing mail server

I want to set it up and I get an uninformative one

Error message.

Outgoing mail server #2:

Name: Postfix

From filtering: mydomain.de

Authenticate with: Username

Connection

Encryption: none

SMTP server: IP address (internal IP of the Odoo server)

SMTP port: 25

Username: root (for testing)

Password: PW from root

Error message:

Invalid operation

One option is not supported by the server:

None

What am I doing wrong?

Best regards