Maytag Side by Side Model MSD2456GE and the bottom fills with ice every day. What could be the cause? More important what's the fix!

My top loading fridge has the same problem. I figured this solution out when I took apart the top compartment to change out the evaporator fan motor. The build up of water on the area next to the coils keeps building up with ice and then melts when it goes through a defrost cycle. I solved my problem by just putting a bowl in the spot where the water drips out of the hole from the top compartment to the regular fridge below. Would suggest that you monitor your system when it goes into the defrost mode and see just where the water is dripping from. Me, I can live with emptying the bowl every day until I have to replace the fan motor again. IF you can't stand emptying the water bowl then call up a repairman and have him diagnose your problem properly. May be something small like a defrost switch failure or a faulty defrost heater.

The drain hole is frozen or plugged. Take the shelves out of the freezer and take the panel at the back off. There should be a hole that the water drains into. Use hot water to clear the hole. Do not use a screwdriver or something like that to break up the ice. If you put a hole in the coils then you have a real problem. You could also just unplug it and leave the doors open for a day.