Mouse Scroll Reverses Randomly: What to Do

Random reverse movement is easiest to diagnose when you separate consistent wheel motion from the events the browser receives.

Look for a repeatable reverse signal

Start the Scroll Wheel Test and make a calm, continuous roll. Its first event sets the expected direction, so repeated opposite-direction events are visible without relying on memory.

Rule out common external causes

Check battery power, receiver placement, cable and USB port, then repeat in another browser. Review mouse utility and accessibility settings only after the same result has appeared in a controlled sample.

Compare another device

A known-good mouse on the same computer can show whether the behavior is device-specific. If reverse events follow one mouse across systems, record the repeatable result before seeking support.