Adding Shared Mailboxes to Web Email
If you have access to a shared mailbox, it will automatically show up in the Outlook desktop program. However, it will not automatically show up in your web email. You can add it manually
Open your OTC web-based email in the browser of your choice. You can get to it through MyOTC, or by visiting http://outlook.office.com
Right-click Folders, and select Add Shared Folder.
In the prompt, type the name of the shared mailbox you wish to add. Then, click Add.
You should now see your shared mailbox in the left column of your web email.