Recently my Windows 7 64-bit has found an unknown device in the category of USB controllers. It was not able to find any driver neither on my computer, nor on Windows Update servers. At the same time Bluetooth support and device disappeared.

Simple logic suggests that somehow Windows has lost information about Bluetooth driver and now recognizes it as unknown USB device. Moreover, afaik my internal Bluetooth is connected through USB interface to the main board.

Any suggestions? What should I do to diagnose the problem? How do I fix my Bluetooth w/o reinstalling Windows?

Hardware: MacBook Pro 15" (6.2, mid 2010).

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    Have you tried reinstalling the drivers offered by your Bluetooth adapter's manufacturer? Have you tried a System Restore back to a point before this happened, to see if it works as expected? – Ƭᴇcʜιᴇ007 Nov 23 '11 at 20:18
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    Does the MAC still have OSX installed? Does bluetooth work in OSX if so? – Paul Nov 23 '11 at 22:47
  • @Paul Thanks. Actually after I rebooted into Ubuntu and OSX and checked my device it worked there. After another reboot back to Windows it started to work in it as well. Apparently that was some kind of firmware issue and either OS X or Ubuntu reset Bluetooth device into a working state. – Sergiy Belozorov Nov 23 '11 at 23:43
  • @techie007 I have installed drivers with Boot Camp. No, I have not tried reinstalling them. Also I have not tried to use System Restore. If I will experience such problem I will try your advice before rebooting into OSX to see if this would have any effect. – Sergiy Belozorov Nov 23 '11 at 23:46
  • @Paul You can add your advice as an answer and I will mark it as such. – Sergiy Belozorov Nov 23 '11 at 23:49

Your MacBook has a Broadcom BCM92070 bluetooth card which is actually an USB dongle. (it's sometimes soldered on some "hybrid" Wi-Fi+Bluetooth mini PCI-e cards but they work separately; see the linked question at the end if you're curious)

That "dongle" requires a firmware to be loaded before it can be used, and it appears that some communication with it (what exactly ? I don't know) may brick it until the next poweroff (a reboot won't do). Once bricked it appears as an unknown device (hardware ID says USB/UNKNOWN) with USB PID 0000 and VID 0000, and further communication with it is not possible.

In your case your system may have updated drivers and during this update (before the device loaded its firmware) it somehow bricked the card. Rebooting into Mac OS (or Ubuntu) unbricked the card by loading the correct firmware on it (Mac and Linux have a different way of detecting USB devices and they somehow manage to detect a bricked card, where Windows just says "unknown device"), so it appears again using the correct USB PIDs & VIDs and Windows can load the correct driver (and firmware) for it.

Related question with a more detailed answer of mine for future readers trying to make this card work on Windows machines.

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    Wow! That answer must have taken some time to do the research. Thanks for putting that much effort. I've marked your answer as an answer to my question. – Sergiy Belozorov Sep 13 '14 at 14:51
  • @SergiyByelozyorov you're welcome. Actually now that I think of it your Macbook may have a slightly different configuration and has no Wi-Fi card, just the BCM92070 crap dongle soldered somewhere on the board. I'll edit out the irrelevant Wi-Fi part (it's still there in the linked question for anyone interested). – user256743 Sep 13 '14 at 15:11

Rebooting into Ubuntu and then Mac OS X helped. Supposedly Ubuntu and/or Mac OS X have reset the device into working state, while Windows was not able to handle the native MacBook firmware.


Go to the unknown device in

Device Manager, Properties / Details and select Hardware IDs from the dropdown

You should see a four hex digit vid and pid. If you do a search in google for these, and it shows up as your bluetooth device, then you know the unknown is the bluetooth device, and it is a case of finding and re-installing the drivers.

If the unknown device isn't your bluetooth device, then the likely answer is that the bluetooth device is broken, as it is not being detected properly.

If you confirm bluetooth is working in OSX, then we know the bluetooth module is fine, so it remains a Windows issue with drivers/firmware.

  • Hardware ID for the unknown device contains USB/UNKNOWN. Bluetooth device is not broken as it works both in MacOS X and in Ubuntu on the same machine. I am not sure though that this device is my Bluetooth, it just looked suspiciously that new device appeared same day that my Bluetooth disappeared. – Sergiy Belozorov Nov 23 '11 at 23:42

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