If you're trying to get Train Simulator to run but can't get it to load up properly, here's a list of potential fixes. Fingers crossed one of them works for you! In my case the game loaded as far as opening a black window for the game, not actually loading anything, then minimising itself. I spent hours trying different fixes and digging through the forums, so now I've put together a list of all the fixes I found which worked for some people who had problems loading it up. I've also included what fixed the game for me which I didn't see mentioned anywhere in the forums.

Have the game closed then try running it after trying each possible fix from the list. Try both the 32 and 64 bit version of the game if you have a 64 bit copy of Windows as some people can only get one to work. Steam needs to be running in order for the game to work.

1. Making sure you've updated to the latest graphics driver and quit NVIDIA RTX voice (if you use it). This worked for me. RTX Voice was conflicting somehow. If the game worked for you before but doesn't now, ask yourself what changed between then and now. Try closing everything else running in the background in case something is conflicting.
2. Deleting the PlayerProfiles file and the two SDBCache files (found in Steam > steamapps > common > RailWorks > Content). Delete those three files.
3. Verifying game files (right click on Train Simulator in your games library > Properties > Local files > Verify integrity of game files).
4. Replacing the OpenAL32 file (found in Steam > steamapps > common > RailWorks > Install > OpenAL > 32bit). Copy the OpenAL32.dll file and paste it into the RailWorks folder. Select replace file.
5. Running Steam as administrator and running the game application in the RailWorks folder as administrator (right click > Run as administrator).
6. Going into offline mode on Steam before launching the game (in the Steam menu, Steam > Go offline).
7. Uninstalling workshop content and DLC. If it works, start re-installing the DLC and then the workshop content until you work out the specific item causing your problem.
8. Re-installing the game (after uninstalling through Steam, delete the entire RailWorks folder if it's still there to remove everything) then restart the PC before trying to launch the game.
9. Someone said they got their game working by re-installing Steam but I didn't try this.
10. I also saw some people saying that their version of Windows 10 caused them problems, so maybe try rolling back to a previous update it it comes to it, or try running the game in compatibility mode for another version of Windows.

Hope this helps! If something else works for you that's not on this list, let me know.