Exchange Server 2010 includes a new feature that can automatically load balance the provisioning of new mailboxes across multiple mailbox databases.  Although the Exchange administrator can still specify a mailbox database if they want to, it is no longer mandatory and the Exchange server can make the decision as to where to provision the new mailbox instead.

This is useful in many different scenarios such as:

  • Simplifies the help desk role of creating new mailboxes by removing the need for help desk staff to choose an appropriate mailbox database
  • During bulk mailbox provisioning or mailbox migrations the mailboxes are automatically spread over all available mailbox databases

Despite the benefits there are also situations in which the Exchange administrator would not want mailboxes automatically provisioned on a particular database.  For example a mailbox database that is configured with a very large mailbox storage quota for VIP users should be excluded, or a new mailbox database that is still in the process of being configured for use should be excluded.

To exclude a specific Exchange Server 2010 mailbox database from automatic provisioning use the following command in the Exchange Management Shell.

[PS] C:\>Set-MailboxDatabase -Identity "Mailbox Database 04" -IsExcludedFromProvisioning $true

To re-enable the mailbox database for automatic provisioning set the value back to $false.

[PS] C:\>Set-MailboxDatabase -Identity "Mailbox Database 04" -IsExcludedFromProvisioning $false

About the Author

Paul Cunningham

Paul is a former Microsoft MVP for Office Apps and Services. He works as a consultant, writer, and trainer specializing in Office 365 and Exchange Server. Paul no longer writes for


  1. matan

    Hi Paul, is there an elegant way to migrate mailboxes from 2010 to 2016 (from a list of mailboxes) to specific databases with automatic distribution to get a balanced migration?

    thank you

  2. Marco

    Hello Paul,

    Thanks for the nice article. Although I set for all mailboxdatabases (except the one I want a standard mailboxdatabase) the Values for Isexcludedfromprovisioning and issuspendedfromprovisioning to “true” it does not work. I create the mailbox trough the ECP Webstie and Exchange still chooses a Databse randomly accross als healthy and available databases. Do you know if there is any Service I need to restart? I also checked AD Replication, but there seems to be anything alright.
    Maybe it is because the target mailboxdatabase is on a different site?
    Thanks a lot


  3. teboho

    i am using exchange 2003 with server 2003 in my virtual environment and i cant exclude the auto mailbox creation when i create a new user in AD can you please help i want to create the mailbox when the user has a certain attribute for example department ..then the mail box should be autocreated in AD.

    1. Avatar photo
      Paul Cunningham

      This feature was introduced in Exchange 2010. It doesn’t exist in Exchange 2003.

  4. kranthi

    Is there a way to restrict mailbox database to provision mailboxes in Exchange 2007 environment. I am aware that we don’t have this parameter in Exchange 2007.

      1. Anthony

        In this case, is there a way to restrict mailbox creation permissions to only certain users to be able to create mailboxes on certain Exchange 2007 mbx databases?

  5. v-9basa

    we have exchange 2013 sp1

  6. v-9basa

    Hi Paul,

    I was testing isexcludedfromprovisioning true for a database…if that is set, we cannot move existing mailbox also to that database. actually in production we have three databases and we want new users only in one database excluding other two…if I set the isexcludedfromprovisioning true for other two databases, that works but I also cannot move mailboxes to these two databases….anything we can do for it..please help

    1. Avatar photo
      Paul Cunningham

      Possibly a bug, as that is not how the feature is documented to work. I see the same issue in my Exchange 2013 CU6 test lab.

      1. v-9basa

        Thanks Paul. any work around plzzzz.


      2. v-9basa

        Hey Paul,

        I want your advise regarding hosting. we have e2k13 sp1 cu6 and now we want to host one domain…what is your advise, should I go for third party control panel or manually do the things.. Please advise

  7. Mike

    Hi Paul,
    Thank you for the article, but I got an issue with that.
    When I set IsExcludedFromProvisioning = $False for one of my databases (and also IsSuspendedFromProvisioning = $False) I do not know why but after few hours my database IsExcludedFromProvisioning status is switch back to $True.

    Do you know what could be the reason of this?

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