Specifically, its called "bluetooth usb host controller". code 28, drivers were not installed. there are no compatible drivers. i tried bootcamp 5.1.5621 and 5.1.5722 drivers.. I have upgraded to windows 10 from windows 7 on bootcamp on my imac. when checking device manager it shows the yellow exclamation mark against the bluetooth usb host controller. "update driver" shows no available driver.. Right click on bluetooth usb host controller-> bluetooth settings-> tick allow bluetooth devices to find this pc and click apply, ok. click add a device . now, all bluetooth devices will be displayed and paired with the windows correctly..
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