HP Notebook scroll Not working

It's possible the touchpad itself is dirty. Since we use our fingers to move the mouse around, the likelyhood of it getting dirty is quite possible. So you should clean it off. However, be sure to shut down your computer first and make sure it's cold. then use warm water and a damp washcloth and lightly wipe it down... let dry and try again. It doesn't matter how clean your hands are, our fingers are constantly producing oils to keep our skin alive. This oil is transfered onto everything we touch, and in the case of touch pads can bulid blocking the sensor confusing your finger's actions. In other words, it's sensor can't detect what you're trying to do. Try this first, if it doesn't work... replace the driver. However, since your mouse isn't working properally.... you'll have to download the driver software from another computer and put it on an SD card.