When you say "flashes empty" is that the flashes on the charger? If it's blinking slowly on multiple batteries then it isn't charging them correctly. If something is showing up on the camera screen when you switch it on, then I think you can rule out the battery door as the problem. If I recall, the camera won't do anything if the door isn't shut properly. Look and make sure the contacts for the battery inside the camera's battery slot is clean and has no corrosion issues.