If you have been given access to another user's mailbox, here are the steps to viewing it:

  • Login to Outlook on the web at https://outlook.office.com with your own credentials
  • At the top right-hand corner, click on your initials (or profile picture) and choose Open another mailbox
  • Type in the last name of the person whose mailbox you want to view
  • The name should appear in the list - click it and click Open

The mailbox will open in another tab.