Mystery Mouse Appearing in Bluetooth Menu of Mac Mini after Wipe and Fresh Install

[Engender]

Just got a used Mac Mini. When I got it, the seller had set up a dummy account. I booted into recovery, erased the physical disk (which contained two Macintosh HD-data drives), and then reinstalled Big Sir. I believe this should be sufficient for a complete wipe and reinstall.

However, under the Bluetooth menu, there is an option for someone I've never heard of's mouse. Presumably, the previous owner's mouse.

How could that have survived a complete wipe and reinstall? Was there more that I should have done?

 

[DeltaMac]

You should be able to mouse across that strange bluetooth device, click the "X" to remove it from the list.
I think other devices that have either connected, or just scanned as a possible connection, and get retained by the firmware.
I commonly see unknown devices show up on bluetooth on a variety of Macs, and the boot software apparently doesn't decide what is retained.
Keep in mind that bluetooth devices are extremely limited for connection distance, so bluetooth devices that you don't know about, are simply useless phantoms that you should be able to remove.

 

[Boyd01]

How far away is your nearest neighbor? Could it be their mouse? I've been surprised at how far bluetooth signals can travel sometimes.

 

[Engender]

If it were a neighbor, I would have seen it on my Mac Pro (with the updated Wifi and Bluetooth mod). So, I should just not worry about it, then?

 

[MacCheetah3]

Successfully connected (presumably authorized) BT devices as well as the selected startup disk, chosen display resolution, and a few other tidbits are stored in NVRAM. It’s necessary so you can execute boot commands (e.g., Option, Command + R) with a wireless keyboard.

You should be able to go to System Preferences -> Bluetooth -> hover over the device and click the “X” to the right (as @DeltaMac mentioned) to remove it. Then forget about it.


And if you are actually curious, macOS shows you the “Connected” status below the device name in that panel.