Add a Shared Mailbox in Outlook
If you notice that you are missing a shared mailbox or you have requested for a shared mailbox and it does not appear in your outlook window. You can add it by doing the following whilst in outlook.
1. Right click on your Email Address just above Inbox
then click on Data File Properties...
2. In the General tab, click on Advanced...
3. Go to the Advanced tab and click on Add...
then type in the mailbox you want and click OK
4. Mailbox appears in previous window. (to add more click Add... and follow step 3)
click Apply and OK and OK on next window
5. Mailbox now appears in your outlook Left Pane