Product review (5 stars): The final trick to fix wafer leaking problem.
I found lot of water below the fridge bottom drawer.  I googled then bought a new drain evaporator DA61-06796A.  However after I replaced it, the next day I still found some minor water below the drawer.  I googled again, then I bent the bottom of this aluminum panel so it will cover the entire drain channel.  The next day I still found some water.  I then found some people replaced this sensor.  I bought it and replaced it.  The next day I found the area below the drawer was dry.  I don't know if this new sensor played the trick or it was the effect of all the changed I have done.  Hopely the problem will not come back.  I will most likely never buy any Samsung products in the future.  I had a simpler American brand refrigerator for 20 years and never had any problem.