If that isn't helping then:
-extract the driver file
-go to device manager
-find your sound card (as a sound card or unknown device)
-look if unknown device is your sound card
-if yes(or your sound card is detected), then install manually
-specify the driver location yourself... In other words have disk and choose the .inf file from extracted driver folder.
And that should do it...I know it's complicated, i don't guarantee a certain success. But I've got most old hardware running with windows 7 and 8, just takes some effort.
Example, my laptop from 2005 runs Windows 8 Pro like a champ.