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Not what you’re looking for? Try Adding a shared mailbox to Outlook for Windows - Instructions for O365 Shared Mailboxes
Instructions for Connect (on-prem) Shared Mailboxes
Open Outlook. Click on the File tab near the top-left corner of the window, and then click the Add Account button.
Type in the email address of the shared mailbox and then click the Connect button.
Click Exchange at the Advanced setup window.
Click the More choices text towards the lower-left corner of the Windows Security prompt window.
Click Use a different account
In the next screen:
the first text box enter your 8-character username @uwaterloo.ca (e.g. j25rober@uwaterloo.ca)
and type in your password in the second text box
Check the box for “Remember my credentials” and then click OK.
A message that the account was successfully added will appear. Click the Done button to close the window.
Close Outlook – wait about 10 seconds – then launch Outlook.
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