I thought the filter needed to be replace, but I didn't have another one so I put the blue plug cap on it. Still no water. Of course this also meant no ice. At first I thought it was frozen but after removing the plastic guard around the area, and pulling the ref. away from the wall and checking the lines, nothing was frozen. Took a chance that it was the filter head so that is was I ordered. Asked for regular shipping and received it in two days! Was able to replace it and it works great now. The only tricky part was figuring out how to remove the water line that goes from the water filter down the back of ref. You have to somehow push down on the light blue ring while pulling the tube out. This took some finangling, but we were able to do it. I could see where this would stump plenty of people however. After seeing the new filter head I realized the very small white plastic points had been "smooched" so when the filter or the bypass cap were put on, the filter head did not recognize that they were there. I have no idea how this happened, but that was the problem. Be sure to look at original installation before you tear it out, there are no instructions with the parts, but the shipping was incredibly fast and part worked beautifully!