Exchane 2013: Change the Location of the Queue Database

1. Create the folders where you want to keep the queue database and transaction logs. Make sure that the correct permissions are applied to the folders.

2. In a Command prompt window, open the EdgeTransport.exe.config file in Notepad by running the following command:

Notepad %ExchangeInstallPath%Bin\EdgeTransport.exe.config

3. Modify the following keys in the <appSettings> section.

<add key="QueueDatabasePath" value="<LocalPath>" />

<add key="QueueDatabaseLoggingPath" value="<LocalPath>" />

4. When you are finished, save and close the EdgeTransport.exe.config file.
5. Restart the Microsoft Exchange Transport service by running the following command:

net stop MSExchangeTransport && net start MSExchangeTransport

Note: If the Exchange Transport Service didn’t started again after running above command go to Services  and start it manually

To verify that you successfully created a new queue database and new transaction logs at a new location, do the following:

1. Verify the new database files Mail.que and Trn.chk exist at the new location.
2. Verify the new transaction log files Trn.log, Trntmp.log, Trnres00001.jrs, Trnres00002.jrs, and Temp.edb files exist at the new location.
3. If you can delete the old queue database and transaction log files from the old location after the Microsoft Exchange Transport service has started, those files are no longer being used.

Reference:
http://technet.microsoft.com/en-us/library/bb125177(v=exchg.150).aspx