d3d8.dll

I've installed GP4 at friend's computer...whenever we try to run it, we get the message that the file d3d8.dll is missing. What the hell is this file and how can I solve this problem? The 3D acceleration is enabled and I dunno why this is not working.

is directx 8.1 or better installed ?
if not install directx 9.0
if already installed try reinstalling.

Its a dll for direct3d from directx8.
Just like Caelen said...-> what version of dx do you have? ->have you tried reinstalling?
to add something:
If it is about a low end system (lets say around 1000 mhz), I would stick to directx8.1.
Otherwise i would stick to directx8.1 as well (but you don't have to)
From what i have seen, is that the performance on low end systems really drops with directx9. And on most 'turbo-puters' it gains performance.

ps.
Try to run dxdiag first to see if your directx is working correctly.
Run the tests, and you can see there what version you are running

actually, i would upgrade to dx9 if i were u. better performance. and u will need to upgrade anyway sooner or later when the games utilize the new features

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