Hi, My company has recently setup a new exchange infra on a separate domain (Domain B). We have created trust both ways (Domain A and B), AD objects can be seen from both domains. We have created Mailboxs on Domain B, and trying to link it to the user accounts Domain A. How do I switch to browse to Domain A to locate the users? When selecting browse, I can only go to Domain B. Thanks.

HI In the Exchange Management Console, click Recipient Configuration. In the action pane, click New Mailbox. The New Mailbox wizard appears On the Introduction page, click Linked Mailbox, and then click Next. On the User Type page, click New User. On the User Information page, complete the fields. On the Mailbox Settings page, complete the fields 5. 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 and finish for further information : http://technet.microsoft.com/en-us/library/bb123524(EXCHG.80).aspx wish it will be helpful regards