The game defaults to later versions of DirectX, however some older systems may not be compatible.
Until recently, players could run the game in DX9 mode instead, however support for this version of DirectX has been discontinued.
If you previously were using launch parameters to run the game in DX9 mode, try removing the DX9 parameter now and running the game without it.
If needed, you can instruct Steam to run the game using OpenGL instead:
- In Steam, go to your Library
- Right Click on the game title
- Select Properties
- Click Set Launch Options...
- Paste the following line into the provided text box
- Click OK, then Close.
You can also launch alternative modes using the .bat files which are located in the game's install folder.