How to Create a Linked Mailbox

Microsoft Exchange Server 2007 will reach end of support on April 11, 2017. To stay supported, you will need to upgrade. For more information, see Resources to help you upgrade your Office 2007 servers and clients.


Applies to: Exchange Server 2007, Exchange Server 2007 SP1, Exchange Server 2007 SP2, Exchange Server 2007 SP3

Topic Last Modified: 2007-04-17

This topic explains how to use the Exchange Management Console and the Exchange Management Shell to create a linked mailbox in Microsoft Exchange Server 2007.

A linked mailbox is a mailbox that is associated with an external account. The resource forest scenario is an example of when you would want to associate a mailbox with an external account. In a resource forest scenario, user objects in the Exchange forest have mailboxes, but the user objects are disabled for logon. You must associate these disabled user accounts in the Exchange forest with enabled user objects in the external accounts forest. For more information about deploying Exchange 2007 in a resource forest topology, see Planning for a Complex Exchange Organization.

To perform the following procedures, the account you use must be delegated the following:

  • Exchange Recipient Administrator role

  • Account Operator role for the applicable Active Directory containers

For more information about permissions, delegating roles, and the rights that are required to administer Exchange Server 2007, see Permission Considerations.

Also, before you perform this procedure, confirm that if you are deploying a resource forest topology, you have completed Steps 1, 2, and 3 in the procedure How to Deploy Exchange 2007 in an Exchange Resource Forest Topology.

  1. In the Exchange Management Console, click Recipient Configuration.

  2. In the action pane, click New Mailbox. The New Mailbox wizard appears.

  3. On the Introduction page, click Linked Mailbox, and then click Next.

  4. On the User Type page, click New User.

    Every mailbox must have a user account associated with it. However, the user account that will access the linked mailbox does not exist in the forest where Exchange is deployed. Therefore, a disabled user account that exists in the same forest as Exchange must be created and associated with each linked mailbox. That is the new user account to which this wizard page is referring.
  5. Click Next.

  6. On the User Information page, complete the following fields. These fields are for the disabled user account that will be associated with the linked mailbox, not for the actual user account in the remote forest that will be accessing the mailbox:

    • Organizational unit   By default, the New Mailbox wizard displays the Users container in Active Directory. To change the default organizational unit (OU), click Browse, and then select the OU you want.

    • First name   Type the first name of the user. This field is optional.

    • Initials   Type the initials of the user. This field is optional.

    • Last name   Type the last name of the user. This field is optional.

    • Name   By default, this field is populated with the user's first name, initials, and last name. You can modify the name in this field.

    • User logon name (User Principal Name)   Type the name that the user will use to log on to the mailbox. The user logon name consists of a user name and a suffix. Typically, the suffix is the domain name in which the user account resides.

    • User logon name (pre-Windows 2000)   Type the user name for the user that is compatible with the legacy versions of Microsoft Windows (prior to the release of Windows 2000 Server). This field is automatically populated based on the User logon name (User Principal Name) field. This field is required.

    • Password   Type the password that the user must use to log on to his or her mailbox.

    • Confirm password   Retype the password that you entered in the Password field.

    • User must change password at next logon   Select this check box if you want the user to reset the password.

  7. Click Next.

  8. On the Mailbox Settings page, complete the following fields:

    • Alias   By default, this field is populated with the user's first and last name, with no space between the names. You can modify the alias in this field.

    • Server   To change the default server, select the server you want from this list.

    • Storage group   To change the default storage group, select the storage group you want from this list.

    • Mailbox database   To change the default mailbox database, select the mailbox database you want from this list.

    • Managed folder mailbox policy   To specify a messaging records management (MRM) policy, select this check box, and then click Browse to select the MRM mailbox policy to be associated with this mailbox. To learn more about MRM, see Understanding Messaging Records Management. This is an optional field.

    • Exchange ActiveSync mailbox policy   To specify an Exchange ActiveSync mailbox policy, select this check box, and then click Browse to select the Exchange ActiveSync mailbox policy to be associated with this mailbox. To learn more about ActiveSync mailbox policies, see Understanding Exchange ActiveSync Mailbox Policies. This is an optional field.

  9. Click Next.

  10. On the Master Account page, complete the following fields:

    • Trusted forest or domain   Click Browse to open the Select Trusted Forest or Domain dialog box. Select the forest or domain that contains the master account, and then click OK. This enables the Browse button for the Linked domain controller field.

    • Use the following Windows user account to access linked domain controller   To access the domain controller in the trusted forest or domain, you can use credentials other than the ones with which you are currently logged on. If you want to specify a different user account, select this check box, and then use the User name and Password boxes to type your credentials.

    • Linked domain controller   Click Browse to open the Select Domain Controller dialog box. Use this dialog box to select the linked domain controller that you want to use, and then click OK. Selecting a valid linked domain controller enables the Browse button for the Linked master account field.

    • Linked master account   Click Browse to open the Select Master Account dialog box. Select the user account that you want to use as the master account for the linked mailbox, and then click OK.

  11. Click Next.

  12. On the New Mailbox page, review the Configuration Summary. To make any configuration changes, click Back. To create the new linked mailbox, click New.

  13. On the Completion page, the Summary states whether the linked mailbox was successfully created. The summary also displays the Exchange Management Shell command that was used to create the linked mailbox.

  14. Click Finish.

  • Run the following command:

    New-Mailbox -Database "Mailbox Database 1" -Name "John Peoples" -LinkedDomainController "DC01fabrikam" -LinkedMasterAccount fabrikam\john -OrganizationalUnit Users -UserPrincipalName -LinkedCredential:(Get-Credential fabrikam\Admin01)

    In this example, the fabrikam domain is in the accounts forest. The user account fabrikam\Admin01 is used to access the linked domain controller.

For detailed syntax and parameter information, see the New-Mailbox reference topic.