Open (Right-click Start button > Device Manager). Look for "Bluetooth" or "Universal Serial Bus devices." If you see a yellow exclamation mark next to an unknown device, right-click and select Uninstall device .

(and its sibling, the BR17) often acts as a rather than a generic Bluetooth adapter.

While generic drivers are recommended, some third-party databases list specific driver files if the plug-and-play process fails: : Offers a scan for Borofone BR21 Stereo Drivers compatible with various Windows versions.