Just for a FYI have had 3 CLX-8640's say reseat or reinstall developer with error code (don't remember code). 2 were black and one was cyan. All three the toner was empty but showing had toner. Last cyan showed 30%. I think I only have 4 or 5 of those and three have done that. Toner feels empty and put a new one in and message stays gone.
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