Bluetooth device still paired after clean install I'm facing some issue with Bluetooth device(s) still paired to my Mac after a clean install.

I'm currently using a 2013 Macbook Pro on Sierra, which was previously used by one of my co-worker for the last year. He switched to another computer and after doing a clean install (internet recovery) he then gave it to me. (Mavericks was installed then I installed Sierra).

So, here it is: he has an iPhone which he had previously paired to the Macbook, along with a magic mouse which he gave to me.

To my big surprise, the other day I saw that in the bluetooth icon has changed, and that his iPhone and the mouse (which I had not used yet) was already paired to the Macbook (mark as connected) without asking anything !
I was even able to browse the files on his own phone...

I'm starting to think I'm facing some serious security issue, or we missed something in the clean install procedure but I did not see anything like that on any site nor anyone talking about this ( except maybe this unsolved old thread explaining a similar problem but the devices were not connected for this one...)

I just want to say that I already tried to:


delete the device from the bluetooth menu (holding Option key > [device name] > Delete but then it connected itself automatically some minutes later)
Shift + Option bluetooth menu > Debug > Reset bluetooth module (same result)
Cmd + Shift + P + R to reset NVRAM at boot (this seemed to work for several days, but then it connected automatically again today, still without asking anything!)


Does this sound familiar to anyone?
Just to clarify, have you tried either of the following:


On the MacBook Pro go to System Preferences > Bluetooth and right-click on the device (his iPhone) and select Remove
On his iPhone, go to Settings > Bluetooth and tap on the 'info' icon on the right of your MacBook Pro  and then tap the Forget This Device option


Doing this should solve your issue. For good measure, I would do both.

If the above steps don't work, try resetting the iPhone settings. Your co-worker can do this on his iPhone by going to Settings > General > Reset > Reset All Settings. However, make sure he has his passcode and Wi-Fi passwords handy.

Finally, if you happen to not be using any Bluetooth devices with the MacBook, you can also turn it off totally from System Preferences > Bluetooth.