Scenario
Email messages sent to Exclaimer are not being delivered (or delivery is delayed) and the Microsoft 365 message trace shows an error similar to this:
Reason
Typically, this scenario occurs if the Mail Routing options in Exclaimer are configured to return messages to the Sender Domain. This configuration tells Exclaimer to perform a lookup for each processed email, passing the processed email back to the server(s) specified within the sending domain name’s MX records.
Resolution
Follow these steps to resolve the issue:
- Log into the Exclaimer portal (portal.exclaimer.com) and Launch your subscription.
- From the header bar, select the cogwheel icon to open the Settings menu.
- Select Mail Flow.
- Locate Mail Routing Domain. You may have to scroll.
- In Domain Name, enter the .omnicrosoft.com domain name - this can be located in the Domain list in the Microsoft 365 Admin Center. This setting is important, and an incorrect domain can result in mail flow issues.
Example:
- Click SAVE to save the changes made.