Hi,
I have a Nikon D3100 which stopped working suddenly. The camera was working OK before. I turned it on the display doesn't turn on and when I look through the view finder I can see an Err blinking. The camera makes a sound like a picture is taken, but there in nothing on the SD card. A repair manual I found says to contact Nikon for this type of error. I tried another lens and a working SD card, still the same problem. Any ideas what it can be?