The administration and maintenance of Microsoft Exchange Server to ensure secure, reliable, and efficient email and collaboration services across an organization.
Can you get the message tracking events with the following cmdlet?
Get-TransportServer | Get-MessageTrackingLog -sender <sender email address> -recipients <users who didn't receive the email> -messagesubject <message subject>
If you can see a delivery event, it means the message is delivered to the user mailbox.
If the user cannot find it in inbox, better have a check whether there is some Outlook inbox rules.
If there is no delivery event, please post a screenshot of the events.
(Don't forget to hide your personal information)
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