I got one of these pieces of $@$*, I found on youtube a solution . Press and hold the freezer and lighting buttons at the same time until you hear a beep, Then press the freezer button 3 times until it reads RD this means refrigerator deforst. It will beep for about 26 minutes. I do this about 5-6 times ( I set a timer to do this) but it works for me. I have been doing this for about 2-3 years now. My wife said when I'm done fooling with this piece of $@$* we'll get another one. I stubborn and it hasn't whooped me yet. Also I have to defrost the ice maker with a hair dryer about every 2-3 weeks. I will never ever buy another samsung product. Good luck.
Mike Wilburn