:confused: The water in my shower stall only won't shut off. I have one knob with two ring controls. The outer ring is for the H&C, the inner ring is supposed to shut it off. They both turn but do nothing. I shut the main water off and it still drips from the shower.

I think the faucet you describe is called a MIXIT, and you can find parts at most Hardware stores like Home Depot. Buy the kit that contains the face plate a stem assembly and the new handles. It is easy to repair.