We have a '95 GE Profile refrigerator, over/under model. Ice and frost form on the lower part of the freezer, just behind the door. Is this caused by a faulty door gasket or something else?

SOURCE: Icing up in bottom of the freezer

machine has a defrost issue, defrost mi metal or defrost timer

SOURCE: 16 month old GE Profile

see if the back wall inside of freezer have ice if so you have to change tiker board or check your doors if closing

SOURCE: Ge Profile ice maker not working

you either have a bad water valve, which it is sticking open or B. the ice maker is not shutting the valve off.

SOURCE: GE Monogram refrigerator/freezer problem/ice dam in ice maker

I have had the same problem with ice forming. I found the problem is from the ice maker. The water fill tube delivers water to a plastic piece that acts like a funnel. The water goes through this plastic piece into the ice maker. Ice forms in the plastic funnel piece causing the water to overflow into the ice bin and freezer.

SOURCE: ice if forming along top gasket area and side of freezer where

If we have ice on the inside of the freezer it means air is being pulled into the box somewhere. The most likely place is the door seal, it sounds like you already checked it, but I would suggest that you look very close at the bottom and aides of the seal too, it could be leaking in air from there. Check the inside liner for cracks and seal them if you find any. Look at the corners of the cabinet to make sure there is not room for air to come in.

Air leaks will lead to frost, it is just hard sometimes to find where it is leaking in.