Bosch DW about 4 years old. Tried the method where you start the wash then open the door interrupting the cycle at about 15 minutes. That actually worked at first, but then the problem kept happening. Called Bosch and they suggested pulling the filter, cleaning that and running a bottle of dishwasher cleaner through it. That cleaned it up but dispenser still didn't open. I finally bought the new dispenser, followed the video instructions and BINGO! Problem solved. Not hard if you can follow instructions.