As part of the installation of Exchange 2016, the local queues that control the inbound mail locate themselves in the Program Files directory where the Exchange Binaries reside. As C: drives are generally a lot smaller than others it is common that over time these queue directories may fill up causing the Server to fail. If a queue location runs critically low on space then all inbound delivery is disabled. The best practice is therefore to relocate these files to a location other than C:. In this example we have used the E:\ which is also where our Database Transaction Logs reside. Navigate to the C:\PROGRAM FILES\MICROSOFT\EXCHANGE SERVER\V15\BIN folder and run notepad.exe as administrator to edit the file EdgeTransport.exe.config Look for the lines that are highlighted below.
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Modify them with the new location and save the file back to the original location.
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After it has been saved, stop and restart the ‘Microsoft Exchange Transport’ service.
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To check that the location has taken effect, check the location and see that the directories have been created. As below.
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No need to restart the Server after this.