After the latest update, upon starting the game, I get an error that says, "The following component(s) are required to run this program: Microsoft Visual C++ 2015 Runtime." This is before anything shows up after Steam's pop-up saying that the game is starting up. I don't play the game often, and this one time I wanted to play and I can't. I am running Windows 10 on an ACER laptop.
Right click on Train Sim World, then click on properties and go to local files tab. then select verify integrity of game files, it will take a few minutes. It will find anything that is missing and re-download it.
That usually fixes that issue yours sounds a little more difficult If have not already done so send a ticket to support.