Logitech dual action gamepad, not working

I can't get my logitech dual action gamepad to work. Its been 3 months since I used it last. The red light comes on and shows that it is plugged in my usb port however my computer does not detect the gamepad, I cannot calibrate it or anything. I tried installing the manufacture's drivers, and that did not help. I have windows vista(I used this controller before on Vista).