This feature requires you to use a Microsoft Exchange account. Most home and personal accounts do not use Exchange.
If you have delegate (delegate: Someone granted permission to open another person's folders, create items, and respond to requests for that person. The person granting delegate permission determines the folders the delegate can access and the changes the delegate can make.) access permission for other Exchange mailboxes (mailbox: Location on a Microsoft Exchange server where your e-mail is delivered. Your administrator sets up a mailbox for each user. If you designate a personal folder file as your e-mail delivery location, messages are routed to it from your mailbox.), you can specify which mailboxes to open in Microsoft Outlook.
- On the Tools menu, click E-mail accounts, select View or change existing e-mail accounts, click Next, select the Exchange account, and then click Change.
- Click More Settings, then click the Advanced tab.
- Under Mailboxes, click Add, and then select the mailboxes to add.