Call me a fool, but at one point I actually unscrewed the keyboard top from the bottom, dumped all the crumbs and dust into the trash, sprayed both sides with windex, rinsed it with cool water in the sink and set it out in the sun to dry. I had spilled a glass of wine on it a few weeks before and cleaned as much of that up as I could, but the keys started sticking after that. My cleaning job fixed everything! I don't recomment this unless you are about to throw your keyboard in the trash. I had nothing to lose; my keyboard was headed for the dumpster, so I said WTH and it worked like a charm.