Overview

When GFI MailEssentials is installed as a Simple Mail Transfer Protocol (SMTP) relay and trying to deliver the emails to the mail server, the Message Delivery Log of the mail server shows in the Status Reply:

550 5.7.1 Message rejected as spam by Content Filtering

Environment

• GFI MailEssentials
• All supported environments

Root Cause

Content Filtering was enabled on the mail server and is blocking emails.

Resolution

Content Filtering has been enabled on the recipient's mail server. This configuration is incompatible with GFI MailEssentials installed as a relay server, all email filterings should happen on the relay server. For more information Content Filtering and how to disable it, please see the following:

If the mail server is Microsoft Exchange 2007 server:

• Content Filtering
• Configuring Content Filtering

If the mail server is Microsoft Exchange 2010 server:

• Understanding Content Filtering
• Enable or Disable Content Filtering

If the mail server is Microsoft Exchange 2013 and 2016 server:

• Content filtering
• Manage content filtering