My iMac wireless mouse is not working. Replaced both batteries turned unit on and off and on but no connection is made. Also the green light does not come on. Sometimes it does sometimes it doesn’t

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Please see: If you can't connect your Magic Keyboard, Magic Mouse, or Magic Trackpad to your Mac - Apple Support.

Jack

My question is similar, however, my mouse WILL connect, however, it doesn't track--the only thing that works is the scrolling with my finger. I have replaced batteries, disconnected and reconnected, turned Bluetooth off and on, but when I move the mouse, nothing happens, only response is when I run my finger across the top. The link in the answer below provided no help at this point. Thank you! Brian

For what it's worth, this is why I do not bother with wireless mice. My wife and I both use cheap wired mice and never, ever have any problems.