How To: Open another user’s mailbox in Outlook Web Access To open another user’s mailbox in Outlook Web Access: Log in to OWA using your own mailbox email address and password. Click on your name in the upper-right corner of the window and click Open Another Mailbox. In the Open Other Mailbox box, enter the email address of the mailbox that you want to open and click Open. The mailbox will open in a new window.
