I have VGA cable output from laptop to PC. It used to black out the laptop screen and display the picture on the TV fine when I plugged the cable into the laptop. For some reason it has stopped doing so. Picture now remains on laptop and TV says no input. Have not changed any settings on either device. Does anyone know what the problem is?
Double check you cables; un plug it, clean it, make sure all the screws are done up tight. If there is still no change, go into windows display settings and see if you get to "choose" between different displays. Even if you haven't changed any settings, windows updates can sometimes change them automatically to make them more "user friendly".