cant find download for sthda.sys?

[weazzel]

my computer randomly stopped sound on most applications. for some reason it still woks on itunes and makes noises and stuff when you navigate folders. i rebooted and started reinstalling my sound but it says i need to download the sthda.sys driver. i dont know what that is at all and have had no luck what so ever trying to find it. here is a screenshot of the install not working.
http://i6.tinypic.com/6yv2jwi_th
sry that image is to small use this
http://tinypic.com/view.php?pic=6yv2jwi&s=1

that img isnt good use this one it is just a screenshot

[Unregistered]

jotsa