Did you Dl a new skin? or maybe you accedently took off the buttons I never worry I got the new lazer mouse (intellmouse 2.0) its amazing so comfortable an I have a back an foward right on the mouse an the scroll is amazing no clicks just strait an smooth it will save you alot time with navagting or you can use backspace to but that only works for back an thats it .
Anyways if your a surfer on the net Id highly recommend the intell its really good.