Your GE GFC320F can leak if its support ring is poorly fitted or not tightened properly. Check your support ring's connection by turning it the left to loosen it. The support ring connects your unit to your sink from below. Make sure it's secured tightly to the flange in your sink hole.
Waste can leak from your sink hole if your disposal unit's sink flange is not properly fitted. Remove the stopper and splash guard from your sink hole. Then turn the mount ring at the top of the disposal unit beneath your sink in a clockwise direction to loosen it. Pull out your unit's sink flange and make sure the flange gasket is correctly fitted. Then reassemble the parts, making sure they are all sealed tightly. If you've used plumbers' putty instead of a gasket, you may need to apply an additional layer around the underside of your sink flange before refitting it.
If your unit's cushion mount is defective or damaged, water can leak from your sink. The cushion mount forms a seal around your sink flange to stop waste water escaping. Inspect your cushion mount for signs of wear or damage. If you find that your cushion mount is the cause of your leak, you'll need to order a replacement from GE.
A leak coming from below your sink hole could be caused by poorly fitted screws securing your unit's discharge elbow to its body. Loosen your elbow flange screws with a screwdriver. Then, screw them back into place tightly. Also make sure there is no damage to the elbow flange itself.