If your Cuisinart grinder has stopped working, there are a few possible reasons why. First, check to make sure that the grinder is plugged in and receiving power. If it is plugged in and still not working, the next step is to check the grind settings. Make sure that the grind setting knob is turned to the correct position - if it is set too low, the blades will not rotate correctly and the coffee beans will not be ground properly. Finally, if all of these things have been checked and the grinder still isn't working, it's possible that there is an issue with the motor or switch assembly inside of the grinder. In this case, it's best to contact Cuisinart customer service for assistance.