Status of outbound message delivery is "SOAP response was a nack"
|Knowledge Article Number||000214301|
|Description||As a result of a workflow rule, an outbound message was triggered and send to the configured endpoint but Salesforce failed to send it and the "Delivery Failure Reason" under Setup | Monitoring | Outbound messages shows "SOAP response was a nack". What's the meaning of this message?|
|Resolution||Salesforce expects the configured endpoint for the outbound message to acknowledge (e.g. to return an "ack" for) the outbound message. However there are cases where the message is not acknowledged (e.g. the response is considered a "nack"). This could happen if the target endpoint is too busy to accept the request, or it accepts it but it does not send and ack back to Salesforce.
To determine the specific reason that caused the "nack", the server handling the outbound message on the configured target endpoint should be checked to ensure it sends an "ack" back to Salesforce and that it's dimensioned to handle the load accordingly.