1. If the film is not too big, you can apply some lacquer thinner to it and then scrub it with cleaning ball. 2. Detergent used in textile industry will work (Bottled such detergent is called al). I've tried it. It really works well. 3. Use sulfuric acid. But you should mix it with water before use, otherwise the door will corrode. Immerge the door into the mixed sulfuric acid for a period of time and scrub it with cleaning ball. 4. Firstly, use electric hair drier to blow the film. And them slowly tear it off. 5. Do NOT use something hard （like cleaning ball）to scrub it if you are not sure whether the door is specular or brushed. Or the surface of the door will be damaged. You can wash it with hot water and scrub it with a stick coated with cotton cloth at the same time. It will work if you do it slowly. If it doesn't work. You can find someone specialized to do the surface processing. 6. Pour some gasoline on a piece of cloth and slowly wipe the door with it.
