EHLO says localhost when send through GSuite OAuth2

“Email is being sent from a domain or IP address which isn’t registered in your G Suite account.”

So I looked, and the cause could be:

“The domain with the configured policy isn’t specified either as the SMTP sender (mail from:<user@domain.com<user@domain.com>>), or as the HELO argument (helo domain.com <http: domain.com>).”

source

That discussion:

220 smtp-relay.gmail.com ESMTP b187sm5252374ith.0 – gsmtp
EHLO localhost
250-smtp-relay.gmail.com at your service, [1.2.3.4]
[…]
550-5.7.0 Mail relay denied [4.3.2.1]. Invalid credentials for relay for
550-5.7.0 one of the domains in: (as obtained from HELO and MAIL FROM).
550-5.7.0 Email is being sent from a domain or IP address which isn’t registered
550-5.7.0 in your G Suite account. Please login to your G Suite account and
550-5.7.0 verify that your sending device IP address has been registered within
550-5.7.0 the G Suite SMTP Relay Settings. For more information, please visit
550 5.7.0 https://support.google.com/a/answer/6140680#maildenied b187sm5252374ith.0 – gsmtp

So do I need to put localhost and/or 127.0.0.1 in the google API settings at GSuite > Admin > Apps > GMail > Advanced > SMTP Relay service? Like:

SMTP relay service
Locally applied
by IP address
Allowed senders: Only registered Apps users in my domains
Only accept mail from the specified IP addresses: Yes
Allowed IP addresses: localhost (IP: 127.0.01)
Require SMTP Authentication: No
Require TLS encryption: Yes
<hr/>

? What are others doing to get the plugin to work?

Thanks!

• This topic was modified 7 years, 3 months ago by Bogus Exception.