3785893 - AS2 MDN Processing Error – Negative MDN with "unknown-trading-relationship"

•    During AS2 message processing, the following error is observed:com.sap.it.rt.adapter.as2.api.exception.MDNProcessingException: Error while parsing MDN, cause: Negative MDN received with error: unknown-trading-relationship
•    The system receives a negative MDN (Message Disposition Notification) indicating failure in message acknowledgment.
•    Message transmission appears successful from the sender system, but the acknowledgment received is a negative MDN.
•    No functional acknowledgment is generated by the partner system.
•    Message retries may continue to fail with the same MDN response.
•    AS2 headers (AS2-From, AS2-To) in the transmitted message do not match the values expected by the receiving partner.
•    Communication channel connectivity remains successful, indicating the issue is related to partner configuration rather than network connectivity.
•    In some cases, messages signed or encrypted with unexpected certificates are rejected and returned with a negative MDN referencing an unknown trading relationship.

SAP Traceability Hub (SAP TH)

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