Trackpad works just fine on Mac book, but take across the hall to my iMac and it is not discovered.
Maybe the bluetooth is inactivated in the iMac.
The trackpad won't be discovered until it has disconnected from the other machine. The range on bluetooth is suppose to be 10m /33.3ft.
The easiest way to disconnect is to power the trackpad off by holding the power button for 5 seconds. Then power on next to the other system.
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