https://blogs.unity3d.com/2017/07/10/deprecating-directx-9/
Support for Direct X 9 in Unity has ended as of July 10th - you're going to have to update your OS or use third party DX10 options that have been available for XP for years. (https://www.raymond.cc/blog/easily-install-and-download-directx-10-for-windows-x...)
Good luck fellow Autonoaut!!!