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Ran into this today - solution for me was simpler than above, just requiring the screen connect to be added to the security * privacy tab.  

System Preferences > Security & Privacy >Privacy > Accessibility

Search for the Screen Connect app from the search window and click Open

Check it's added to the list of apps


As I had view access - I managed to get this done by a remote user, and as soon as it was done I had full control again.  No need for reboots etc..