The Exchange 2016 installation will create a System Mailbox. The normal location is in the C: along with the system binaries that make up Exchange. This is generally not a desirable place for this to be located and a much better location would be alongside the databases that would be used for mailboxes of connecting users. Therefore to move them away from the C: we just need a few system powershell command. Firstly we want to check the name of the database and it’s current location. This is done with the following powershell command.
get-mailboxdatabase | select name,edbfilepath,logfilepath | fl
Which will produce output as below.
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As you can see from the screenshot, the next task is to give it a better name. I have chosen System DB01 for this. The full command is
set-mailboxdatabase “Mailbox Database 0647524308” -Name “System DB01”
Now we can move it. On the Server I have built, I provisioned two additional volumes. Firstly and E: to hold the transaction logs for the databases and an F: for the databases themselves. To move the System Database I would use the following command.
move-databasepath “System DB01” -EdbFilePath “F:\Database\System DB01\System DB01.edb” -LogFolderPath “E:\Logs\System DB01”
The move process will temporarily dismount the database during the move, so please be aware of that if there are production mailboxes using it.
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As a final check, run the powershell command that views the paths again to confirm it is in the new location.
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And you are done. No need to restart the Server or any services.