The new version of outlook does not automatically display shared email inboxes that you have access to like the old desktop version of outlook did.
1. Open up new outlook
2. Hover over the section in the left menu that is your email address until three dots appear
3. Click the three dots
4. Choose the "Add shared folder or mailbox" option
5. A pop-up will appear asking to enter in the mailboxes to add
6. Once you start typing, a suggested list will appear. When you find the one you want, select it.
7. Hit the "Add" button once you select the email account that you want to add.
8. Repeat steps 2-7 for any additional email accounts to add once at a time with limitations to add multiple at once.
9. The shared mailboxes are now mapped.
10. To go to the mapped shared inbox, expand the carrot ">" next to your inbox and is to the left of your email username.
11. Once expanded, scroll to the bottom of your folders where you will see "Shared with me"
12. Expand the carrot ">" next to "Shared with me"
13. A list will now appear with all the shared mailboxes that you just added.
14. Ability to pin shared inboxes to favorite list for a quick spot to see is being rolled out currently by Microsoft and may or may not have that feature. If you do, then right click the folder or click the three dots next to the folder name when you hover over it and there will be an option in the menu that pops-up to "Add to Favorites"