Windows Vista and 7 only come with DX10/11 installed. While they're supposed to be backwards compatible, they don't always load older games without issues due to missing files.
In this case, as cdrsubron7 said, you need to let it install a Windows 7 compatible version of DX9.
I ran into this situation with Aliens vs Predator and their fubar DX10/11 implimentation which forced me to go down to DX9. To use DX9, I had to install a Vista compatible version of DX9. After that, things worked perfectly and I could switch back and forth at will.
|