The scroll wheel rotates inside a transparent plastic piece. Remove and clean the transparent plastic piece with alcohol, both sides. The optical sensors infrared light needs to cross the plastic piece and the wheel. If the plastic is dirty, the scroll wheel won't work. The dirt comes inside easy from the wheel. Make sure that the tiny slots inside the wheel are clean too, they look like bicycle wheel spokes.
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The scroll wheel rotates inside a transparent plastic piece. Remove and clean the transparent plastic piece with alcohol, both sides. The optical sensors infrared light needs to cross the two windows on the plastic piece and the wheel. If the plastic is dirty, the scroll wheel won't work. The dirt comes inside easy from the wheel. Make sure that the tiny slots inside the wheel are clean too, they look like bicycle wheel spokes.
The scroll wheel rotates inside a transparent plastic piece. Remove and clean the transparent plastic piece with alcohol, the optical sensors infrared light needs to cross the plastic piece and the wheel. If the plastic is dirty, the scroll wheel won't work. The dirt comes inside easy from the wheel. Make sure that the tiny slots inside the wheel are clean too, they look like bicycle wheel spokes.
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The scroll wheel rotates inside a transparent plastic piece. Remove and clean the transparent plastic piece with alcohol, both sides. The optical sensors infrared light needs to cross the plastic piece and the wheel. If the plastic is dirty, the scroll wheel won't work. The dirt comes inside easy from the wheel. Make sure that the tiny slots inside the wheel are clean too, they look like bicycle wheel spokes.
The scroll wheel rotates inside a transparent plastic piece. Remove and clean the transparent plastic piece with alcohol, the optical sensors infrared light needs to cross the plastic piece and the wheel. If the plastic is dirty, the scroll wheel won't work. The dirt comes inside easy from the wheel. Make sure that the tiny slots inside the wheel are clean too, they look like bicycle wheel spokes.