MTW2 install/startup problem

hey guys.
i just found my old MTW2 game, and am trying to play it.
it says it downloaded fine but when i try to start it up i get an error message.

it says:

"This application has failed to start because D3DX9_30.DLL was not found. re-installling the application may fix this problem".

naturally i tried to reinstall it, and it still says the same thing.

any help would be great.

i have vista FTW. not sure if that is the problem or not.

1. bah, i now realize i should have posted this in the apothecary. sry, been awhile.
2. it is a direct X issue. i installed/re-installed direct X, and now it is working.
3. im all good now. thx