In my experience, Plex crashing is most often caused by malformed/damaged video files.
You would need to verify each video file by playing it in VLC or Windows Media Player, skipping through the entire file.
I’m not aware of any programs that can check a video file for errors etc.
You could also try re-encoding the video files using Handbrake or similar or simply replace them with known good files.
Check your Plex Media Scanner Analysis logs for errors showing which files you should target.
Once you have removed/corrected the bad files, your server should stop crashing.
You should probably uninstall Plex and use a freshly downloaded installer package to re-install Plex with.
That would eliminate a bad installation or damaged installer package as the problem.
Logs are always welcome though.
