How to request a Receipt
That way, when the recipient downloads your message from his or her ISP's e-mail server, you receive a message indicating that your e-mail was delivered. In addition, you can request a read receipt, which notifies you when your message is opened by the recipient.
After you create a new message, completing the To and Subject fields and typing the message text, on the Options tab, in the Tracking group, click the dialog box launcher:

The Message Options dialog box opens.
- To request a delivery receipt, click the Request a Delivery Receipt for This Message check box to select it.
- To request a read receipt, click the Request a Read Receipt for This Message check box to select it.

Click the Close button and send the message as usual. When the message is delivered and/or read, you'll receive a confirmation e-mail message.
Note: If you've requested a receipt but don't receive one, it doesn't necessarily mean your message wasn't delivered or read. Some e-mail programs do not send delivery or read receipts.
See also this tip in French: Comment demander un reçu.