I just got done with a chat session with Lexmark. The tech advisor indicated that there is a locking mechanism inside the cartridges that cannot be circumvented; it prevents the cartridge from being refilled and reused. So the refill industry is either committing fraud by selling refills that it knows won't work for this product, or they are unaware that a problem exists! Doubtful! I am not happy about buying a printer and then getting "locked in" to buying their cartridges at a premium price. Goodbye, Lexmark. I won't be buying any more of your products...Is this what you wanted in terms of customer satisfaction?