For Microsoft Exchange only. The message latency test runs a PowerShell script which sends test messages between servers and color-codes the results so that you can see which servers can communicate quickly and which servers may be struggling. The results of the test will show up on the Dashboard under Key Metrics, Exchange Heat Map

Go to Servers & Devices -> Mail -> Message Latency Test
Click the checkbox to the left of the server to enable monitoring
Enter the desired value(s) for the Yellow and Red Thresholds
Click Save to save the settings

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