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Delivery notifications

RFCs

RFC 5337: Internationalized Delivery Status and Disposition Notifications

Alaa 22 July 2026

Extends DSN and MDN formats to support internationalized addresses.

RFCs

RFC 3464: An Extensible Message Format for Delivery Status Notifications

Alaa 22 July 2026

Defines the machine-readable DSN format used in bounce messages and delivery receipts.