Microsoft Exchange Server gateways generate reports to inform message originators of the success or failure of message delivery and receipt. Four classes of reports are supported:
A gateway should always generate non-delivery reports when messages cannot be delivered. Successful delivery reports are optional.
Users can request reports and receipts by users on a per-message basis. Gateways should inspect outgoing messages for the following MAPI properties to determine whether reports and receipts have been requested for the message:
PR_ORIGINATOR_DELIVERY_REPORT_REQUESTED
PR_ORIGINATOR_NON_DELIVERY_REPORT_REQUESTED
PR_READ_RECEIPT_REQUESTED
PR_NON_RECEIPT_NOTIFICATION_REQUESTED
Note The PR_NON_RECEIPT_NOTIFICATION_REQUESTED property corresponds to a request for a non-read receipt.
All reports should conform to the minimum required content and semantics of the X.400 specification. Content and functionality beyond that required by X.400 is optional. For example, nondelivery reports often include the original message content even though it is not required by the X.400 specification; if the original message content is present in a nondelivery report, the user can fix addressing problems and resend the message. Places where reports and receipts for Microsoft Exchange Server are different from the X.400 standard are discussed in Deviations from the X.400 Standard.