Insinkerator garbage disposals, in varied models sold by the hundreds of millions by Racine, Wisconsin-based Emerson Electric, chew up most of the food waste that you throw at them, but they can't handle everything. Bones are a no-no, as is stringy waste, such as cornhusks and celery. These and other items get stuck in the rotary mechanism inside the disposal and jam it, and when this happens, the reset button trips and the disposal automatically stops. Sometimes the breaker controlling the disposal circuit also trips. Before you reset the appliance, you have to remove the blockage, and you can do that without reaching inside of it, which is something you should never do.
Unplug the garbage disposal before you do anything else. If it's hardwired, find the breaker and flip it off. If the breaker has tripped, turn it all the way off.
Locate the service wrench that came with the disposal. If you can't find it, a 1/4-inch hex wrench will do.
Fit the wrench into the hole underneath the disposal in the center of appliance and turn the rotor back and forth until it turns freely. It's OK to apply considerable force -- the service wrench is designed to bend before you damage the disposal. If you're using a hex wrench, it will probably also bend before you damage the disposal.
Keep turning the rotor back and forth until you can turn it freely through 360 degrees in both directions. Remove the wrench and locate the red reset button, which is also on the underside of the disposal. Push the button all the way in until you hear a click. If it won't stay, wait 10 minutes and try again.
Restore power to the disposal by plugging it in or turning on the breaker. Turn on the faucet and turn on the disposal. It should now be working. If it jams again, repeat the procedure to reset it. You may have to do this a few times.