To request a read receipt or a delivery receipt for your message:
- Select Message at the top of the message compose pane.
- Select More options from ribbon
- Select Request a read receipt or Request a delivery receipt, or both.
To choose how Outlook on the web responds to read receipt requests:
- Select Settings
> View all Outlook settings. - Select Email > Message handling
- Under Read receipts, choose how to respond to requests for read receipts.