Sending mail - Unable to get Shared Mailbox to show in "From" field (Outlook Online)

1. Select New mail above the folder list. A new message form opens in the reading pane.

2. Click From in the message, and change to the shared email address.

3. If you don't see your shared email address, choose Other email address and then type in the shared email address.

4. Once done, you can proceed to click OK.