I've been troubleshooting this for several days now with several support groups including Logitec and Experts Exchange to no avail.
I have a Logitec VU-0028 logitech hd pro webcam c920 connecting USB that the system will not find. I've reinstalled drivers and scrubbed through the device manager trying to figure this one out. I spoke to Logitec Support and they concluded that the must ne a addin or video/camera device manager issue. I know the camera works as I have tested it on a different system and as a matter of fact it has woirked on this system sometime back.