Everything was working fine until the update. Already been through the help list, camera on/off, deleted preferences etc. has not helped.
Which Camera are you using?
Tethering Nikon and Leica cameras using Lightroom CC 2015 and Lightroom 6 is not currently supported on El Capitan.
Refer Lightroom and El Capitan | Mac OS 10.11
Thank you Akash, I have subsequently discovered this =( busy trying to downgrade back to Yosemite.
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