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An outbound message that has been successfully transmitted will record the following events in order: BEGIN_OUTBOUND_MESSAGE, BEGIN_OUTBOUND_PROCESSING, BEGIN_INVOCATION_TO_NWHIN, END_INVOCATION_TO_NWHIN, END_OUTBOUND_PROCESSING, and END_OUTBOUND_MESSAGE. By analyzing the time differences between BEGIN_OUTBOUND_MESSAGE and END_OUTBOUND_PROCESSING, one can tell how long it took to make a NwHIN request. Failures can occur after any BEGIN event. In the case of failure, a MESSAGE_PROCESSING_FAILED event will be logged instead of the matching END event. Every BEGIN will be paired with either an END or a FAILED event. Note that it is possible for one step in the processing chain to fail and an outer BEGIN/END pair to complete normally.
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