Why didn't I receive a read receipt after I sent a message that requested one in Outlook?

A. You might not receive a read receipt for several reasons. When you send a message in Outlook that requests a read receipt, the message recipient can decide whether to confirm receipt of the message; if the recipient chooses No, you won't receive a read receipt. If the recipient used a preview pane to read the message, then deleted the message without actually opening it, the recipient's email client won't prompt the recipient to send the read receipt. Finally, you won't receive a read receipt if the recipient doesn't read the message of if the recipient's email client doesn't support read receipts.