If you have been given permission to access another mailbox, this should automatically show up for you when using the outlook desktop app. When using outlook online though these additional mailboxes do not show up for you automatically and you will need to manually add them.
Adding an additional mailbox onto outlook online is a simple process though. please follow the below steps:
1. First, please log into www.office.com with your school email address and password.
2. Once signed into office, select 'Outlook' from the home page.
3. Once you have outlook open on the left hand side, right click Folders and select add shared folder as shown in the below image:
4. Enter the email address of the account you wish to add and click ok.
5. if you have permissions to access this account it will now appear for you as an additional account in the bottom left hand side of the screen.
If you have any problems, please contact IT Support.