X-Plane 11
After a Windows 10 update you may end up with these warnings when you run X-Plane 11:
Load Script: extensions/Gatekeeper/Gatekeeper.lua.gfys: |string "core/json.lua.gfys"|:374: attempt to call global 'error' (nil value)
No ACF Loader. Please re-install Gizmo.
The following fix was found on the forums.x-plane.org and attributed to Cameron on the x-pilot forum.
Delete the marker.1 and (if present) the license_db.bin file located in your X-Plane/X-Aviation folder.