As Exchange 2010 has been around for a while, everyone is familiar with the fact that you don’t have to specify a mailbox database when you create a mailbox. Exchange 2010 automatically assigns a database, if one is not given. This is a very good feature in bulk mailbox creations and migrations as the mailboxes will be automatically load balanced across multiple databases.
But, there might be situations where you don’t want a database to be included for automatic provisioning. One typical example is databases dedicated for senior management/VIP or one that has relaxed limits.
Run the command below to exclude a database from automatic provisioning.
Set-MailboxDatabase –identity “DBName” –IsExcludedFromProvisioning $true
To revert the change, run the command below
Set-MailboxDatabase –identity “DBName” –IsExcludedFromProvisioning $false