Mouse does not come on?
mouse does not come on on my Imac
iMac (Retina 4K, 21.5-inch, Late 2015), iOS 10
Wired or wireless?
Changed the batteries?
Keyboard/Mouse – Troubleshooting Wireless
Bluetooth devices become unresponsive
Bluetooth Interference Sources
Bluetooth Interference Sources (2)
If your Wi-Fi is capable of generating a 5 GHz signal, try that.
Restart the computer holding down the command - option/alt - P - R keys before the gray screen appears. Continue to hold until you hear the startup chime for the second time.