Hello, @CC,
Welcome to the Microsoft Q&A platform!
Based on your information, I understand that you are experiencing delays in mail flow rule propagation in Exchange Admin Center. Here are some steps and tips that might help speed up the propagation process:
1.Restart the Microsoft Exchange Transport Service: Restart the Microsoft Exchange Transport service is a common way to force an immediate update of the cache on a Mailbox server. You need to restart the service on each Mailbox server where you want with the Restart-Service MSExchangeTransport cmdlet to forcibly update the cache.
2.Use PowerShell to Apply Changes: Usually, making changes directly through PowerShell can be faster than using the EAC. Here are some useful cmdlets:
a. Create a new mail flow rule
New-TransportRule -Name "RuleName" -Priority 0 -From "user@example.com" -To "user2@example.com" -SetHeaderName "X-Header" -SetHeaderValue "Value"
b. Update an existing rule
Set-TransportRule -Identity "RuleName" -Priority 1
3.Prioritize Rules: Ensure that your most critical rules have higher priority. You can set the priority when creating or updating rules.
Set-TransportRule -Identity "RuleName" -Priority 0
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Thank you for your support and understanding.
Best Wishes,
Alex Zhang