Had mine also for about 2 years and it started to leak from the bottom as well as a few friends of mine. Took the bottom off and checked all hoses. Pulled the zip ties a little tighter but it still leaked. Upon further inspection and running water through it with the bottom off looking up from a glass table, the leak comes from where the water tank mounts to the base. When the bottom of the water tank gets pushed into the base of the unit, it pushes into a valve which goes into the pump. This valve has a seal which can be seen from the top looking down. This is where the water usually leaks from.
Parts can be ordered straight from Keurig.