Hi Chris,
Is the sim just crashing to the desktop without any message or warning whatsoever? If you are getting any message please post it and you might get better help.
Have you installed any add-ons recently? I know you tried in Safe Mode but still maybe there is something conflicting with the sim…
A couple of things to try from a similar thread:
- Delete (or rename) the content.xml file (for me this is found in C:\Users\username\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache. MSFS will build a new one)
(I renamed it to .old and then once MSFS was running I deleted the new content.xml and re-enabled the one I had previously)
- Delete all the scenery index files (for me these are all the files located in C:\Users\username\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\SceneryIndexes) MSFS will rebuild these as well.
Good luck!