3Com NJ240FX manual experienced 16 transmission attempts and was discarded. The

Excessive	Total number of frames not transmitted because the frame
	experienced 16 transmission attempts and was discarded. The
	discard will only occur if DiscardExcessive is set to a 1 (in global
	control register).
Multiple	Total number of successfully transmitted frames that
	experienced more than on collision.
Single	Total number of successfully transmitted frames that
	experienced exactly one collision.
Deferred	Total number of successfully transmitted frames that are
	delayed because the medium is busy during the first attempt.

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