Went to run FSX after a fairly long absence and presented with this message when trying to run the game:

https://ibb.co/jybnTs4]

Not physically changed anything with the install since last running the game, other than any official Steam updates.

I initally verified file integrity through Steam, no change then did a complete uninstall (including deletion of all subsidiary folders) followed by reinstall but getting the same result.

Any guidance on fixing this greatly appreciated.

If i am not mistaken, simply uninstalling does not remove flight sim's files. You have to manually go into the c drive --> program files ---> steam ---> steam apps ---> delete fsx

Even that does not remove everything, there are files in the c drive --> users as well, but I am too scared to mess with those. But thats more for temporary game states, settings, plane that loads in by default, etc. You could mess up your c drive not knowing what you are doing there. Top suggestion is a safe bet though. 

Edited June 4, 20241 yr by Sweetd31

A corrupt logbook file will cause FSX to not start.  

Turned out there was a rogue multi core line in the Steam launcher parameters which I don’t remember putting there. Deleted that to blank and FSX now launches and runs okay, well as much as it does on modern hardware and Windows 10!

I can't start this either. This may be off topic, maybe not. When I try loading the game by Steam and play. it says "Cannot Load game due to side by side configuration..." anybody here know why I am getting this and maybe how to fix this? Help would be much appreciated.  Thank you.

https://steamcommunity.com/app/314160/discussions/0/1734336452593935286/