Bluetooth device suddenly not working with Windows 10? This might be why

Windows 10 Bluetooth
Image Credit: Microsoft

Bluetooth has become an incredibly popular tool for connecting devices, whether it's the best smartwatches or the best wireless headphones. But, not all Bluetooth devices are created equal, and a new security update from Microsoft may break Bluetooth connection for some devices on Windows 10. 

The new security update arrives in a number of Windows cumulative updates, including the update for June 2019. But, it goes beyond that, so it won't just be computers getting the latest major update that are affected. The security update and Bluetooth changes will effect Machines running even Windows 8.1 and Windows Server 12, as discovered by Windows Latest

The security update isn't breaking Bluetooth connections on accident, though. The change is intentional, and it aims to block potentially dangerous devices from connecting to Windows computers. What Windows is doing in this case is blocking connections from Bluetooth devices that use well-known encryption keys. 

You can find more details on all the affected updates from Microsoft here.

What you can do

In most cases, this security update is not going to affect you. Popular Bluetooth devices from major manufacturers aren't likely to have launched with well-known encryption keys. And, in cases where they have, the companies may have updates available to remedy the issue.

If a Bluetooth device you've attempted to connect can't connect, you can check in the Windows Event Log for an error to see if this update is the cause. The error will show up with "BTHUSB or BTHMINI" in the Event Source field, "22" in the Event ID, and "BTHPORT_DEBUG_LINK_KEY_NOT_ALLOWED" in the Name field. 

It will also include the Event Message Text: "Your Bluetooth device attempted to establish a debug connection.  The Windows Bluetooth stack does not allow debug connection while it is not in the debug mode."

If your device is not connecting because of this error, you can either try to update the Bluetooth device or roll back the update. The the other alternative is to replace the Bluetooth device itself. Since future updates of Windows are likely to keep this change to Bluetooth security, keeping insecure Bluetooth devices is likely a fraught option.