Here are a few basic troubleshooting steps that can be taken to resolve issues in Microsoft Flight Simulator:
1. Delete any rolling cache.
2. Delete the Content.xml file.(AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\Content.xml)
3. Delete the simulator .dat files(AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\SceneryIndexes\*.dat)
4. Do not add anything other than the problem product(s) to the Community folder.
If you still experience an issue with one of our products, feel free to submit a Support ticket