Ok I'm having the same issue with ACE not working for the 777-3, I've uninstalled 4 times and I made sure to deactivate my AV & WIN DEF but to no avail. Also my AV popped up when opening ACE see attached. I'm also getting the following message about the ace_777.exe  "This short cut refers to has been changed or moved so the short cut will no longer work properly" my path is the following:

C:\Users\bankh\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\Packages\Community

Please advise?

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