After updating OS X it is usually necessary to trash the prefs. Launch Finder and on the menu bar click “Go” whilst holding down the Optn(Alt) key and choose Library. Open the Preferences folder and trash the two plist files relating to LR6 (see image below)
Then re-launch Lightroom.
N.B. Apple hides the user Library until the Alt key is depressed.
Thank you for that suggestion. Unfortunately, there were NO "LR com.adobe.Lightroom etc" files in the Preferences folder of the Library.
I also did a Spotlight search on all "com.adobe" files and found NO LR files,
I also checked the earlier TM files from before the upgrade to 10.11.4 and there were none there either.
Below is the screen shot of the crash report
Update - actually I did subsequently find those "plist" files under User/Library/Preferences and deleted them.
I reinstalled LR and got the same problem - Error 16
Many thanks for that link - I made the suggested changes, - no luck - still giving the same Error 16 message.
I uninstalled and reinstalled/rebooted several times, but no start-up.
This was a clean install of OS X 10.11.4, everything works but the Adobe products - similar situation with PS.
I would appreciate any other ideas.
I think as it is concerning licencing you need to talk with Adobe directly. Go to this link. Click the blue button; when signed-in with your Adobe ID; then click Chat 24/7. Ignore suggested links, go straight to the blue button.