1. In Outlook, click the "Tools" tab near the top of the window, click the "Accounts"  menu item.

   Open

   

2. Click on the “Advanced“ button

   Open

   

3. Choose the “Delegates” tab as below:

    

4. Under the “Open these additional mailboxes” Click the “+” to get the following dialog window

    

5. Enter the account name in the search field, then select it in the list below, as below:
   
   

6. Click add and you will see the following:
   
   

    

7. Click the “OK” button, and close the dialog windows.

    

1. Open Outlook for the Mac

2. Ensure you are running Outlook using the New Outlook. Toggle the option to ON:

    

3. With New Outlook enabled:

   1. Navigate to File > Open > Shared Mailbox

   2. Enter the 8 character username of the shared mailbox (e.g. sharenam@uwaterloo.ca)

   3. Click Add

4. Your shared mailbox will now be available to use in Outlook for the Mac

Please see the article https://support.microsoft.com/en-us/office/the-new-outlook-for-mac-6283be54-e74d-434e-babb-b70cefc77439 to learn of the many new features. Note that not all features are available yet in the New Outlook for Mac.

You may prefer to continue using the Old Outlook for Mac window design and toolbar ribbon.