4. Creating linked mailboxes
A
linked mailbox is a mailbox that is accessed by a user in a separate,
trusted forest. Typically, you use linked mailboxes when your
organization’s mailbox servers are in a separate resource forest and
you want to ensure that users can access free/busy data across these
forests. You use linked mailboxes with on-premises Exchange
organizations.
All linked mailboxes have two user account associations:
-
A unique user account in the same forest as the Mailbox server. The
same forest user account is disabled automatically so that it cannot be
used for logon.
-
A unique user account in a separate forest for which you are
creating a link. The separate forest user account is enabled so that it
can be used for logon.
In Exchange Admin Center, linked mailboxes are displayed under
Recipients > Mailboxes. In Exchange Management Shell, you can find
all linked mailboxes in the organization by entering:
Get-Mailbox -ResultSize unlimited -Filter {(RecipientTypeDetails
-eq 'LinkedMailbox')}
You can create a linked mailbox by completing the following steps:
-
In Exchange Admin Center, select Recipients in the feature pane and then select Mailboxes.
-
Tap or click New, and then select Linked Mailbox. This starts the
New Linked Mailbox Wizard. A linked mailbox cannot be created with a
forest or domain trust in place between the source and target forests.
-
On the New Linked Mailbox page, tap or click Browse to the right of
the Linked Forest text box. In the Select Trusted Forest Or Domain
dialog box, select the linked forest or domain in which the user’s
original account is located, and then tap or click OK. This is the
separate forest that contains the user account that you want to create
the linked mailbox for in the current forest. Tap or click Next.
-
If your organization has configured a one-way, outgoing trust where
the current forest trusts the linked forest, you’re prompted for
administrator credentials in the linked forest so that you can gain
access to a domain controller in that forest. Type the user name and
password for an administrator account in the account forest, and then
tap or click Next.
-
Tap or click Browse to the right of the Linked Domain Controller
text box. In the Select Domain Controller dialog box, select a domain
controller in the linked forest, and then tap or click OK.
-
Tap or click Browse to the right of the Linked Master Account text
box. Use the options in the Select User dialog box to select the
original user account in the linked forest, and then tap or click OK.
-
Tap or click Next. On the General Information page, the
Organizational Unit text box shows where in Active Directory the user
account will be created. By default, this is the Users container in the
current domain. Select the Specify The Organizational Unit check box
and then tap or click Browse to create the new user account in a
different container. Use the Select Organizational Unit dialog box to
choose the location in which to store the account, and then tap or
click OK.
-
In the User Logon Name text box, type the user’s logon name. Use the
drop-down list to select the domain with which the account is to be
associated. This sets the fully qualified logon name.
-
Tap or click More Options. Type the user’s first name, middle
initial, and last name in the text boxes provided. These values are
used to create the Name entry, which is the user’s display name.
-
Optionally, enter an Exchange alias for the user. The alias must be
unique in the forest. If you don’t specify an alias, the logon name is
used as the alias.
-
If you want to specify a mailbox database rather than use an
automatically selected one, tap or click Browse to the right of the
Mailbox Database text box. In the Select Mailbox Database dialog box,
choose the mailbox database in which the mailbox should be stored.
Mailbox databases are listed by name as well as by associated server
and Exchange version running on the server.
-
Tap or click Save to create the account and the related mailbox. If
an error occurs during account or mailbox creation, neither the account
nor the related mailbox will be created. You will need to correct the
problem.
In Exchange Management Shell, you can create a user account with a linked mailbox by using the New-Mailbox cmdlet. You’ll be prompted for the credentials
of an administrator account in the linked forest. Although with earlier
releases of Exchange you needed to set a password for the related user
account, this is no longer required.
