Lost control of sound - Trojan Virus

Hello,

I lost use of my sound after finding out that I had a Trojan virus. I can still get to the prompts, but I am unable to activate the sound or add the icon to my desktop. I have a Dell Inspiron 1520. Even though I have no "sound", when I get an email or open outlook explorer, I get a loud beep-type sound like a smoke detector! So, obviously, my computer is still capable of making sound.

Any help would be greatly appreciated!

Thanks...