I just upgraded (?) from Lightroom 5 on a Mini Mac to Lightroom CC on my new iMac.
When I plug my camera in to upload photos, a few will import then the camera will no longer be 'seen' by my computer / lightroom.
I've gotten it to work again after re-launching the program or my computer. It stopped but is now happening all the time. (Like 3 photos will upload and then it quits).
How is your camera connected to the computer?
Have to tried to copy the images from the camera to your computer and then importing them to Lightroom?