1. Sign into your account on Office365.
2. Browse to the Outlook app.
2. Click on the profile picture in the top right-hand corner and select Open another mailbox....
3. When the Open another mailbox window appears enter the name or email address of the shared mailbox and click on Search contacts and directory.
4. When the confirmation of the shared mailbox appears, click Open.
The shared mailbox will now open in a new tab.
