|So, are you going to tell us what your E drive is? Look in Windows Disk Management to determine what it is. If it is an external drive it will indicate it.|
Most digital cameras have 2 on positions. The first is for taking photos, the second is for accessing the files on the camera or removable memory.
Are you certain the USB port you are connecting to works?
Are you somehow trying to connect your camera directly to the E drive?