Not all print services may be capable of delivering interesting events, or even telling when a job is complete. This message indicates the print job has no further information or communication with the print service. This message should always be delivered if a terminal event (completed/failed/canceled) is not delivered. For example, if messages such as JOB_COMPLETE have NOT been received before receiving this message, the only inference that should be drawn is that the print service does not support delivering such an event.