The Multipart/Report Content Type for the Reporting of Mail System Administrative Messages (RFC 3462) - The Multipart/Report Content Type for the Reporting of Mail System Administrative Messages

The Multipart/Report Multipurpose Internet Mail Extensions (MIME) content-type is a general "family" or "container" type for electronic mail reports of any kind.  Although this memo defines only the use of the Multipart/Report content-type with respect to delivery status reports, mail processing programs will benefit if a single content-type is used to for all kinds of reports.
This document is part of a four RFCs set describing the delivery status report service.  This collection includes the Simple Mail Transfer Protocol (SMTP) extensions to request delivery status reports, a MIME content for the reporting of delivery reports, an enumeration of extended status codes, and a multipart container for the delivery report, the original message, and a human-friendly summary of the failure.