My mouse won't connect to my iMac

If you have an Apple Magic Mouse, plug it into your iMac with a lightning -> USB cable. It will automatically pair it to your iMac.

Of course, make sure your mouse is turned on.

Right, MD_1991 maybe i can help you. If you have one of Apple’s recent magic mice with a lightning port on it, it should have come with a usb to lightning cable. Turn off your mouse, plug in the cable.. and plug the usb end of it into your iMac. Then turn it on again and it should work as a usb mouse.. bluetooth anything can be finicky and fussy on startup/in recovery mode.. eg they don’t always connect 100% of the time super-reliably..

good luck.. and it’s apple + R keys held down together on keyboard on startup for recovery..

option+apple+R gets you internet recovery

john b