I had the same problem and found that the problem was that my file manager was showing the "preview panel". You can switch it off by going up to the little icon on the top to the left of the question mark.
maybe there's an other software on your computer that accesses your digital camera. Just check that all programs are closed, when you connect your camera to the PC. You can also try to use the TaskManager to verify that there are no running applications.
To launch the TaskManager just use the following shortcut: "Ctrl + Alt + Del".