You are using Exclaimer Cloud, and start to receive bounce-backs from sent messages, with a similar non-delivery report:
This issue is caused by messages looping between Exclaimer Cloud and G Suite, when routing via the Content Compliance rule and our server, usually because of header conditions not matching.
To resolve this issue, you need to correct the header conditions of the Content Compliance rule.
G Suite Super Admin credentials
To correct the header conditions:
- Login to the G Suite Admin Portal.
- Navigate to Apps > G Suite > GMail.
- Click on Advanced Settings.
- Locate your Content Compliance rule, by default this will be called Route to Exclaimer Cloud.
- Click Edit.
- Edit the Rule to match the below:
- Ensure that the Content field contains:
Not Contains Text X-ExclaimerHostedSignatures-MessageProcessed
- Click Save.
- Click SAVE at the bottom of the page: