And whether the game can run normally before.

And which plug-ins were installed after the last run before the game crashed.

Possible reasons:

System problem, unable to solve, reinstall the system.

Registry problems, you can try to use the registry to repair the software, if not, reinstall the system.

System problem: nothing like it. Net or DX9 is installed.

Game problem: the game is castrated. Please download the full version of FSX again.

Game problem: There was a problem during the installation.

Hardware problem: The hardware is not enough to run FSX.

Plug-in problem: Plug-in crashes the game. For example, PMDG737NGX SP 1b, after I installed it, I often crashed playing games.