Scenario: You have permission to another users mailbox and you want to open that mailbox via Outlook Web App (OWA)
- Sign in to your account in Outlook Web App.
- On the Outlook Web App nav bar, click on your name. A list appears.
- Click Open another mailbox.
- Type the alias or email address of the other mailbox that you want to open. Another Outlook Web App session opens in a separate window, allowing access to the other mailbox.