Monitoring undeliverable/dsn/ndr for highly critical mailboxes?

Question

We are running an Exchange Hybrid solution between Exchange Online and Exchange Server 2019. We need to figure out a way to monitor if someone tries to send mails to one of a select few highly critical mailboxes where it was not delivered for whatever reason. My initial thought was to create a transport rule, search for the postmaster sender and do a regular expression match for the e-mail addresses. This was not possible. I then tried various variations where I searched for "Undeliverable " in the subject line and similar. This does not work either. I then found out that because it is a system message transport rules does not apply.

I then figured maybe you could create an alerting policy in Exchange Online, but apparently these are also quite limited.

I'm now down to have to use a powershell script to look at the mail flow and then send a mail based on this. But I really prefere something I can implement through the graphical interface.

Does anyone know of a way to let our supporters know if delivery of a mail to a select mailbox have failed? Preferably without powershell.

Thank you! :-)

Answer 1

Microsoft is positioning the "priority accounts" feature for such scenarios: https://techcommunity.microsoft.com/t5/microsoft-365-blog/using-priority-accounts-in-microsoft-365/ba-p/1873314

Answer 2

@Melmix

The most convenient way is to use PowerShell and Task Schedule to check and send email automatically.

If you want to use GUI to check it, you could use "Message Trace" function in new Exchange online admin center(But, you need to check it manually):

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