Speakers/audio aren't working

A while ago my dad had to reset everything on our computer because of some really annoying virus, and now we have no audio. He's had to reset it before because of the same virus, but back then there was no problem with audio. It seems I have all the right things plugged in for the speakers, but when I go to Control Panel and all that, it doesn't recognize that I have anything hooked up. Suggestions?

I've gone 2-3 months without audio on computer, really sucks :/

Open up device manager and check if there's a ? by something that sounds like it has something to do with sound. If there's a ? next to something that has to do with sound your going to need to download the sound drivers for your computer. This can be done off the makers website.

Give me your computers maker and model and I'll post a link to the sound driver.

Thanks guys, I just downloaded the sound driver and everything works great.