1. Open Outlook:
Select “Tools” then choose “Account Settings”

2. From This Screen, double click on “Microsoft Exchange Server”

3. Select “More Settings…”

4. Click the “Advanced” Tab

5. Click Add
Type in the name of the mailbox you want to add
Click ok
Click “Apply” and “ok”

6. Choose Next:

7. Select Finish
The Mailbox will be added to your outlook