Multi-tenant emails can't be sent internally - 550 5.7.64 Relay Access Denied

Epicor ERP 10
1

We are running on a multi-tenant shared cloud version of Epicor. When we try to email from the Epicor system, we get a security error “550 5.7.64 Relay Access Denied ATTR36” from the Epicor cloud server. We are using Office 365.

People outside our domain get the emails but no one internally receives the email except for the reject email which goes to the system admin’s email address.

This is the mail system at host aushossmtpprd01.activant.com. This is the server trying to send the email.

Epicor set our SMTP server at 10.161.4.141 and Port 25. Any help would be greatly appreciated.

Epicor has not been very helpful on this one.

Thanks

2

I very much doubt that any of us can help you in MT SaaS. This is very much an Epicor Support EMS Call…

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3

Thanks Jose. What does EMS stand for? We’ve tried normal Epicor support and have been told it’s an IT issue on our part.

4

At least a year ago, EMS and the Cloud Team were two separate departments. When we left single tenant, we moved from Epicor Managed Services to the Cloud Team.

5

This is not an Epicor hosting issue.

If you throw the SMTP error message into Google, you will get a number of hits - most of them relating to the configuration of Exchange Online Protection (EOP). Consider the cause of the error - the Epicor SMTP server is sending an email from someone at your company to someone else at your company and yet the source of the email (the Epicor SMTP Server) does not match your Email Server. According to EOP, clearly someone is trying to impersonate one of your employees so the message is rejected.

From the Google posts, it looks like you will need to work with the Office 365 Folks to configure EOP to allow what you want.

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