Add Shared Mailbox to Outlook

In Outlook click ‘File’, and then click ‘Add Account’

Enter the name of the mailbox in ‘Your Name’ section, and enter the email address of the account.  No password is required.

Click Next and you should be prompted for a password in a separate window.

Enter the password sent in the email and click OK.

Restart Outlook.

Once open you should see the additional mailbox in the left-hand menu.