Something else must be wrong because there is no "support" for JPEG images. They are simply supported inherently because of the format. Adobe doesn't have to do anything to support JPEG images from any camera. When you say that Lightroom Will not read files from your camera, what are you doing? How are you trying to read the files?
Downloading direct from cameras is the most problematic way to get files to your computer. I suggest you buy a quality card reader and use that.
Can you Copy and Paste the files from the Camera to a folder on your computer???
The USB cables with cameras are not usually the best quality it seems.