I my 5d Mkiii is recognized on Lightroom 5.6 but will not capture Tethered. It does read the camera in Canon utility and captures so it is not a hardware or cable issue.
Make sure the Canon Utility is closed when you are attempting to tether.
The Canon Utility is closed.
It worked before on Lightroom in fact I had to upgrade my OS to the current 10.9.6 to get it to work.
Troubleshoot tethered capture in Lightroom
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