Mail Flow Rules Exchange (2019) - Haven't worked reliably (or at all) for years

Question

Hello,

im using exchange 2019 on Premise and have always had problems with the rules in Outlook products and especially the mail flow rules in Exchange.

-We create a message flow rule in the Admin Center

-This rule is active and works. We are also testing it. It works with various emails, even after 10 minutes. Everything is OK at that point

-After period X (p.a. 45 minutes), the rule suddenly stops working even though it is still listed as active

-I can now do the following: deactivate and activate the rule OR change something in the rule and save

-After that, the rule works again, but only for a short time before the problem returns.

This is not a special rule. As a test, we had if the mail comes from an external recipient, then add a prefix to the subject. At some point the rule stops applying. We had these problems years ago, but then we didn’t bother with the rules any further. Even with the rules that the clients themselves create in Outlook, there are partial problems. No idea if our installation has a problem or what it is

Greetings

Answer 1

Hello, @JoseBernandes,

Welcome to the Microsoft Q&A platform!

Based on your description, you are experiencing an issue with your Exchange 2019 mail flow rules.

To troubleshoot, ensure your Exchange server is up-to-date with the latest patches, and check the Event Viewer for any errors around the time the rule stops working. Restarting the transport service and using the Exchange HealthChecker tool can also help diagnose and resolve issues. Additionally, review the rule configuration and priority to ensure there are no conflicts.

For client-side rules in Outlook, make sure they are correctly configured and not conflicting with server-side rules. Repairing the Outlook profile or recreating the rules might help. You can click on Repair Outlook Data Files (.pst and .ost) - Microsoft Support for instructions. Verifying server health, ensuring sufficient resources, and checking for custom transport agents can also aid in identifying the underlying problems.

Moreover, a document on How to Resolve Outlook Rules Not Working is here for your reference: Outlook Rules Not Working? 8 Fixes to Try.

(Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.)

Should you need more help on this, you can feel free to post back. 

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If the answer is helpful, please click on “Accept answer” as it could help other members of the Microsoft Q&A community who have similar questions and are looking for solutions.

Thank you for your support and understanding.

Best Wishes,

Alex Zhang