How to force Mac (Yosemite) to use USB Bluetooth instead of internal? I'm on an older Mac Pro, and I bought the ASUS USB-BT400 so that I can use Yosemite's Handoff feature. The problem is, I don't know how to disable the internal Bluetooth and force my machine to use the USB Bluetooth instead. I searched around but didn't find anything that worked.
To force your system to use an external Bluetooth controller instead of the internal one, open Terminal and type: 

sudo nvram bluetoothHostControllerSwitchBehavior=always


then reboot. To revert to the default OS X behavior, type:

sudo nvram -d bluetoothHostControllerSwitchBehavior


You may need to turn off (or un-pair) Bluetooth accessories that are currently using your internal Bluetooth controller, as they can prevent the dongle from being detected by the Continuity Activation Tool.