My Grid is also showing the error in DX 12 and I did the following process:
1 - I went to the Grid installation folder: - 😄 \ Program Files (x86) \ Steam \ steamapps \ common \ GRID (2019)
2 - There is the executable "Grid_dx12" only. I copied and pasted it in the same folder and renamed it to "Grid_dx11" and now I am able to play normally. PS: I don't know what the logic or meaning of what I did. It just did and it worked for me. I created a shortcut on the desktop and only run the game for it.
- Ryzen 7 2700x
- RX5600 XT 6Gb GigaByte
- 16 Gb Ram Ba