I have owned one for 6 months and I am having a problem with the water being pumped to the top and dispensing. No matter what cup size dispensing does not occur, yet I can hear the motor continuing to run. I have an e mail in to Keurig since my machine is still under warranty. If they can't resolve my issue one way or the other, I will not purchase a Keurig again. I have descaled twice in the past 6 months, most recently two months ago and that does not solve the problem.
I too have this same problem. Bought the machine December 7, 2012 and last night February 13, 2013 it broke. Goes through the whole cycle but water does not dispense. I think Keurig is a huge fraud because they have no way for one to purchase replacement parts. I will never buy keurig again.
Mine was doing this. After 5 or 6 attempts to clean etc, I unplugged, removed the water tank, took it outside, tipped it upside down and gave it a good shake. Turned it up again and water started to dribble from the nozzle. Fitted it all back together, and it works again. Small blockage moved.
Had the same problem, used a paper clip to unclog the part where the water come through (the metal pointy part that pokes the hole in the k-cup). Didn't have much success until I kept doing it and ran water through and then *as water sputtered through, I lifted the handle to make it stop, then put it right back down to resume.* each time coffee grounds came out little by little until POP the clog came out and water poured out. It's now working great!!!