Hi. Ahead of wall-mounting the TV I removed three of the four back plate screws with the alan key provides without any issues. The fourth screw would not move. Our electrician (who happened to be in our house doing some other work) also tried but could not remove the screw. It looks like there is no "thread" for the key or any screwdriver to work. Any ideas? The TV works fine but we cannot put it on the wall.
