Sign in to the Microsoft 365 admin center
Go to Exchange admin center
Select Mail flow
Open Message trace
Choose a date range
Enter sender, recipient, or message ID if available
Run the trace
Review the message status and delivery details
Open the trace result for more details
Use extended message trace for older or more detailed results
Export the results if needed
Use PowerShell with Get-MessageTrace for advanced tracing
Use Get-MessageTraceDetail for event-level details
Verify the message is not delayed, failed, filtered, or quarantined
Check quarantine and transport rules if the message is not delivered