At my wits end! These are the devices:
Windows 7 pro x64 on a lenovo thinkpad w541.
Sony mdr-zx770bn bluetooth headset
I can 'pair' the devices (inasmuch as an 'MDR-ZX770BN' icon shows in Devices and Printers). But drivers are never located. I get "bluetooth peripheral device - driver not found". In Device Manager, I get three new yellow-flagged devices in the 'other devices' category.
Sony's website says there are no drivers for this headset (implying, I suppose, that I should use the built-in Windows drivers). Their website explicitly mentions that this headset is supported by Windows 7.
Contacted Sony chat support and wasted about 45 minutes with them, other than to confirm that indeed there are no Sony drivers for this headset, and that indeed the headset is supported by Windows 7. They told me to contact Microsoft.
Microsoft's website has information on this error message: obtain the driver from the peripheral's manufacturer.
I'm now stuck in FPP (finger-pointing purgatory).
However I found one ray of light. I found a couple of threads in various forums that recommend manually updating the drivers of the unknown devices to use the Microsoft "Standard serial over Bluetooth link". I did so, and now Device Manager sees four new entries under Ports (COM and LPT): four different instances of the serial-over-bluetooth driver, each using a different COM port (COM4, COM5, COM6, COM7).
I did a properties of the headset's bluetooth icon in Devices and Printers and found that FOUR services were enabled for this device: Audio Sink (COM5), Handsfree Telephony (COM4), Headset (COM7) and Remote Control (COM6).
Unfortunately, even though the headset is paired and now has some drivers assigned to it, and no yellow-triangles or red-Xs appear in Device Manager, the headset does not show up as an audio device in Windows (microphone or speaker). Even after power cycle and re-pairing.
Maybe the bluetooth radio driver needs updation? I have Intel bluetooth radio (USB\VID_8087&PID_07DC). Windows update said I had the latest version but I was able to find a newer version (19.0.1621.3340). After installing that driver, nothing changed for better or worse.
There's also a Microsoft bluetooth enumerator. I haven't tried to find a newer version of that. It is currently at 6.1.7601.17889
that's where I stand now.
I suspect one solution is to buy a USB-Bluetooth dongle, but I'd like to solve this with the native hardware if possible.