The steps are the same, as in the 2010 world.

 

As in Exchange 2010, installation of 2013 Mailbox role creates a new mailbox database with a name “Mailbox Database *”, where * represents a long number. Exchange administrators prefer to follow a naming convention and keep things clean.

Default mailboxes in Exchange 2013

Easiest will be to rename the default database to something that suits your naming convention. Click the Edit button and rename the database & hit the Save button.

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