If a sales order is created or updated by a 'Sales - EDI order to Order' or 'Sales - XML order to Order' message, the message is added to the EDI history (with direction 'Inbound' and type 'Order'). If an applicable document flow with direction 'Outbound' and type 'Acknowledge' exists, also a record is created in the Outbound message queue. When this record is processed, the 'Sales - Acknowledgement to XML' message is run. As a result, this message gets the data from the EDI history record as defined in the outbound message queue record and creates and sends an EDI acknowledgement message file to your customer. For the related record in the EDI history, the Acknowledgement status is set to Sent.