I bought this for my oceanside vacation rental last October. I placed it on a protected patio area and placed the key in it. It worked fine until last week when a guest absolutely could not get the key out. I sent my handyman over, who knew the combination. He tried it. Didn't work. Tried it again. Didn't work. Sprayed WD-40 on it. Didn't work. He never got the key out of there. Fortunately, I had a back up lock box that did work. My back up lockbox was a cheapo that had been sitting out in the tropical rain for 18 months. That had to be sprayed with WD-40, too, but it opened. I have no idea what went wrong but my guess based on previous reviews is the following: 1) it rusted, or 2) it was inadvertently reset.