Install bug report Dx10

Hi High’s
I try a new install on brand new PC and there is a persistant warning message “direct 9c is not yet installed”.

Patchs running likely well… and there’s amazing FFdshow icones on tray with many option on right-click…

Is anybody can explain me what about ?

thanks
an eternal newbie

Set up:
N’vidia GeForce 9800GT (pilote from 27.03.2009)
Dx 10
MS framework 3.5 (include 2)