Standard Serial over Bluetooth link (COM39) Driver

The Standard Serial over Bluetooth link (COM39) driver lets Windows use a virtual serial port to communicate with a paired Bluetooth device that supports serial connections. Associated with Microsoft’s Bluetooth support, this component is useful when connecting compatible scanners, instruments, GPS receivers, or other equipment through COM39 rather than a physical serial cable.

Key Features

• Virtual serial communication: Provides a COM-port interface for compatible Bluetooth devices and software that use the Serial Port Profile (SPP).
• Application connectivity: Lets programs select COM39 as their communication port, provided the paired device has an appropriate Bluetooth serial service.
• Windows integration: Works with Windows Bluetooth components and the computer’s Bluetooth adapter driver to support serial connections.
• Device management: Appears in Device Manager, where you can check its status, troubleshoot errors, or request a driver update. COM39 is an assigned port number, not a separate hardware model.

How to Install Standard Serial over Bluetooth link (COM39) Driver

1. Check your Windows version. Listed operating systems include Windows 10, 8.1, 7, Vista, and XP. Confirm compatibility with your Bluetooth adapter and system architecture before choosing a package. For Windows 10/11 systems, do not assume an older download supports Windows 11.
2. Look for the appropriate driver source. Before starting a Standard Serial over Bluetooth link (COM39) driver download for Windows, check Windows Update and your computer or Bluetooth adapter manufacturer’s support resources. This virtual-port component is commonly supplied through Windows rather than a standalone COM39 installer. Use a trusted free download source if an additional adapter package is required.
3. Install or update Bluetooth support. Install the compatible adapter driver if needed. Alternatively, open Device Manager, locate the Bluetooth adapter or affected serial-port entry, and use the driver update option to search for an available driver.
4. Pair and configure the device. Enable Bluetooth, pair your equipment, and confirm that it offers a serial service. If necessary, use Bluetooth settings to add the appropriate incoming or outgoing COM port.
5. Verify the connection. Check the assigned port under “Ports (COM & LPT)” in Device Manager, then select that port in your application. If Windows assigns a number other than COM39, use the actual assignment and the equipment’s recommended communication settings.

Keep Bluetooth support updated through trusted channels, choosing the latest version compatible with your operating system and adapter. An update may resolve connection issues, but pairing, port selection, and application settings also matter when troubleshooting serial communication.

Common Issues and Fixes

• Install fails or driver won’t load: This is a Microsoft in-box Bluetooth serial driver, so avoid installing a second Bluetooth stack. Run Windows Update and the Bluetooth troubleshooter, restart, then remove and re-pair the device.
• Device or COM39 not detected: In Device Manager, check Ports (COM & LPT) and enable Show hidden devices. Remove stale “Standard Serial over Bluetooth link” entries, confirm Bluetooth is on, and re-pair. The assigned COM number may change.
• COM port/version conflicts: Re-pairing can create duplicate incoming/outgoing ports. Open Bluetooth settings > More Bluetooth options > COM Ports, remove unused ports, and select the correct one in your app. If a legacy app only accepts COM1–COM9, reassign COM39 to a free lower port.