Is there a definitive way of telling when a user opened a specific e-mail message with Outlook 2003, apart from receipts or read/unread marks ? It's a request from HR to determine when an employee actually read a certain e-mail. No receipts were attached to the e-mail by the sender and e-mails can be marked read or unread by a user, so there's no definitive proof there. Thanks. Using Exchange 2003 on the back-end.