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I am not from Laminar Research; just a flight simmer from down under.
You haven't attached your log.txt file or indicated what version of X-Plane you are running. or if your version is a digital download or a disc version.
Have you recently uploaded X-Plane 11.40? If you have then you have uploaded a Beta version which is still in development/ testing phase before the official release.. Current Beta version is Beta 9 and the official advice I received today from my Laminar contact is the beta version will continue for some time while fixing known or advised bugs. Seriously consider viewing the following link for future reference created by an experienced X-Plane flight simmer found at https://forums.x-plane.org/index.php?/forums/topic/160879-thinking-of-downloading-a-x-plane-beta-version/
If you are not an experienced X-Plane user as the link advises you should not dabble in Beta versions. Leave that for the X-Plane experts.
It is also known that some aircraft capable of running on XP11.36 will not run on the current XP11.40 beta version.
Now with regards to your current Mac running the Catalina OS. The other bad news from Laminar in the last 24 hours is that Macs will have problems with XP11.40. Laminar is and has been aware of problems for some time between XP and Mac. They are working on a solution.
On the presumption you have upgraded to XP11.40So and if you want to continue running X-Plane and had no problems before any updates or upgrades. then change back to the last official release of X-Plane 11.36 for public/general use.
The only way I know of a "back version" installation that has worked for me is to:-
You will then be using X-Plane 11.36
Because of little information I had to make a number of presumptions.
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