To open a mailbox you have been granted permission to in the Outlook Web App (OWA) in Office 365, please do the following:

  • Login to Office 365 at
  • While logged in to Office 365, in the upper right hand corner click the image of the person and click "Open another mailbox".


  • Begin typing the email address of the mailbox you want to open, then click the suggested mailbox from the list.
  • Then click Open to open the mailbox in a new tab.