Flip the disposer over and unscrew the electrical cover plate on the bottom of the disposer by removing the cover plate screw. Again, be sure the power to the unit has been turned off at the electrical supply panel. Then disconnect the electrical cable connector. Pull out the wires and remove the wire nuts. Also unscrew the ground wire from the green ground screw. Be sure to save the electrical cable connector so you can use it again.
At one point, I did have a leak that I eventually determined was due to improper installation. (This was by the same "professional" plumber who reversed the hot and cold supply lines when installing a kitchen faucet. He just didn't connect the drain hose properly.) While investigating the issue, I called Waste King to inquire about possible in-home service or warranty replacement. I was blown away by their level of customer service: no waiting on hold, just an immediate connection to a person who really knew the product and was unexpectedly diligent in resolving my problem -- which, as it turns out, wasn't even their fault.
Another common cause for a leaking garbage disposal is the disposal flange. A leak at the very most upper area of the garbage disposal could be the garbage disposal flange which goes through the sink. A garbage disposal flange should be sealed with Plumber’s putty and then tightened from underneath the sink. If this is not tight enough or if it has managed to come loose (which can happen) then the garbage disposal will have to be taken down so the flange can be resealed and then the garbage disposal can be rehung.