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Helo command rejected: Host not found

I'm trying to configure my outlook account to send email through my
mail server, but I receive the following error:

InvalidRecipientsException: Invalid recipients were provided for the
message: ' ... at cerm dot unifi.it' (450 4.7.1
<HE1PR1001MB1369.EURPRD10.PROD.OUTLOOK.COM>: Helo command rejected:
Host not found

Is there a way to put *outlook.com in a "white list"?

Comments

Re: Helo command rejected: Host not found

By Viktor Dukhovni at 10/09/2017 - 10:15

That would presumably be the STARTTLS submission service on port
587, or perhaps smtps (TLS first then SMTP) port 465.

Wrong question. Instead don't filter the helo command at all for
authenticated submission users. See the commented out sample
master.cf configurations (from the stock master.cf file
distributed with Postfix source) in:

<a href="https://github.com/vdukhovni/postfix/blob/master/postfix/conf/master.cf#L17" title="https://github.com/vdukhovni/postfix/blob/master/postfix/conf/master.cf#L17">https://github.com/vdukhovni/postfix/blob/master/postfix/conf/master.cf#L17</a>

<a href="https://github.com/vdukhovni/postfix/blob/master/postfix/conf/master.cf#L29" title="https://github.com/vdukhovni/postfix/blob/master/postfix/conf/master.cf#L29">https://github.com/vdukhovni/postfix/blob/master/postfix/conf/master.cf#L29</a>