About 2 weeks ago, my computer indicated that I didn't have a sound device. It just disappeared. I managed to get my SigmaTel sound device up again, but when I click on the box to put the volume control icon in my taskbar, I am told that it isn't installed, and I don't know where to find it to install it. When I try to go to SigmaTel, I get errors. I think I may have accidentally deleted some important things on my computer but I'm not sure. Can anyone help?