On Demand Access to Delegated Accounts

To add another user's mailbox to your Folder List:
  1. In Outlook 2016, from the File tab, select info, and then click Account Settings
  2. Click new email.
  3. Enter your name and the email you have permission to delegate without entering in a password.
  4. Click OKNext, and then Finish. You should now see the other person's mailbox in your Folder List with the shared folders listed beneath that mailbox. If you can't see the Folder List, select View, and then Folder List. If you cannot expand the folders in the other person's mailbox, check with the mailbox owner to determine whether you have permission to access the
    folder you're trying to open.