If you have a big brand computer like HP, Dell, Gateway, Emachine, etc.. Chances are you can find the missing driver on the manufacturers website. Most of these sites have an option where you select your computer model and it gives you a list of all the drivers used. Just try to find it, unzip, install and reboot. If your driver isn't found, atleast you know the name of it so you can try googling it. I don't mean to offend you with this question, but have you tried looking at the Advanced Sound options in the Control Panel? I've seen some cases where the device just got disabled. You can also check if it's been desabled by right click on "My Computer" then go to "Manage" then "Device Manager". I hope some of this helps. Let me know how it turns out.