I returned to the customers house this morning. I checked that the water line was turned on under the sink. Then I checked to make sure that water was coming to the filter. It was. Then I checked to see if the water was leaving the filter. It wasn't! I checked the filter and I don't know how it happened but the filter was in backwards. I put the filter in the correct way, and bingo, water at the dispenser. So hopefully, the problem is solved!