Hi this is Otto age 12 from from Hong Kong here and I have exactly the same problem; rear port propellor will not stop - and we have not crashed this drone either ...just went like this on a charge...only bought it yesterday with ALL my pocket money from the past 6 months !! Very unhappy. My Dad (who is not an engineer) has spent hours trying to re install the software, and then find a Parrot service centre in Hong Kong - in his words it seems "they are very happy to sell you one and then try and sell you another but service the things - no way". My dad may not be an engineer, but he is a lawyer and Parrot SA may in his words about to get: "a rocket propelled drone...with law suit attached" if this turns out to be a wide spread problem and they make no effort to look after the kids who work hard save their money and buy these things that do not work. Anyone from Parrot interested to provide a solution - or are they too busy selling the things to ensure they work?