- On Microsoft Exchange Server 2003 grant the requesting user full access to the additional mailbox as follow:
- Open Active Directory Users and Computers and navigate to Domain Users.
- Right-click on user account you want to monitor then click on Properties.
- Go to Exchange Advanced tab and click on Mailbox Rights.

- Add your account to the list and select Full Access check box, then click OK.
- On your computer close Microsoft Outlook.
- Open control Pannel and double click on MAIL.
- Click on Email Accounts and select the current exchange user account from list, then click Enter.
- Click the More Settings Button and then go to Advanced tab.

- Click on Add button and select the additional mailbox from global list, then click OK.

- Click on Finish and close window.
Now the user has access to the added mailbox should appear in the left panel when opening Microsoft Outlook..