Here are some potential fixes you could try:

1. Redownload the depot (A file could have been corrupted during the install. Make sure to delete or rename the bad install in the depots folder because that can cause other problems)

2. Delete your save files (For some people new save files on the old version cause issues for some people. Hit Win + R on the keyboard and paste this in %LOCALAPPDATA%\fnaf9\Saved\SaveGames that’s where all your saves are located)

3. Just keep trying to open it (For whatever reason the game can just crash on boot so try a few times and maybe it will work)

Anyways those are all the potential fixes I can think of now. If this doesn’t work join the discord and ask in run help for help. Hopefully one of these fix the issue though!