Ugreen Bluetooth 5.0 Usb Adapter Cm390 Driver ((new)) -

The Complete Guide to the UGREEN Bluetooth 5.0 USB Adapter (CM390): Drivers, Setup, Troubleshooting & Alternatives

Introduction: Why the UGREEN CM390 Remains a Top Choice

In an era where desktop PCs and older laptops still lack native Bluetooth connectivity, the USB Bluetooth dongle remains one of the most cost-effective upgrades you can buy. Among the crowded market of adapters, the UGREEN Bluetooth 5.0 USB Adapter (Model CM390) has carved out a reputation for reliability, range, and driver stability.

However, like any hardware, the “plug-and-play” promise often collides with the reality of Windows driver conflicts, missing Linux firmware, or macOS compatibility hurdles. If you have searched for the term “UGREEN Bluetooth 5.0 USB Adapter CM390 driver,” you are likely facing one of three scenarios: ugreen bluetooth 5.0 usb adapter cm390 driver

You just bought the adapter, and Windows failed to auto-install the driver.
The adapter is recognized but won’t scan for devices (or keeps disconnecting).
You are trying to get it to work on Linux, older Windows builds, or macOS.

This article will serve as the ultimate resource. We will cover the chipset information, official and generic driver sources, step-by-step installation guides for Windows 10/11, tweaks for Linux (Ubuntu/Debian), Android compatibility, and a detailed troubleshooting section.

Q4: Does unplugging the CM390 remove the driver?

A: No. The driver remains installed. Just plug it back in. However, on Windows, pairing information is stored per adapter – if you use the dongle on a different USB port, you may need to re-pair devices. The Complete Guide to the UGREEN Bluetooth 5

Step-by-Step for Ubuntu/Debian-based distros:

Plug in the UGREEN CM390.
Open a terminal and run:
```
dmesg | grep -i bluetooth
```
You will likely see “firmware not found.”

Download the firmware from Realtek’s GitHub repository:

sudo apt install git
git clone https://github.com/Realtek-OpenSource/rtl8761bt_firmware
cd rtl8761bt_firmware

Copy the firmware files to the correct directory:

sudo cp rtl8761b_fw /lib/firmware/rtl8761b_fw.bin
sudo cp rtl8761b_config /lib/firmware/rtl8761b_config.bin

Reboot or reload the Bluetooth module:

sudo modprobe -r btusb
sudo modprobe btusb

Check with bluetoothctl – you should see the controller listed.

For Arch Linux: Use the rtl8761b-firmware package from AUR.

Note: Some Linux distributions (Fedora 38+) include this firmware by default. Try a live USB first. You just bought the adapter, and Windows failed

Installation notes (Windows example)

Plug adapter into USB-A port (prefer rear-panel USB on desktops for stable connection).
Wait ~30–60s for automatic driver install; check Device Manager → “Bluetooth” or “Other devices”.
If device shows with warning or as unknown, download vendor driver and run installer or update driver manually (right-click → Update driver → Browse).
After driver install, enable Bluetooth in Settings → Devices → Bluetooth & other devices.
Pair devices via Windows Bluetooth settings.

Issue 4: Blue Screen of Death (BSOD) – “rtbt.sys failed”

Cause: Corrupt driver installation or conflict with another Bluetooth stack (e.g., Intel or Toshiba stack). Solution:

Boot into Safe Mode.
Use a driver cleaner tool (like DriverStore Explorer) to remove all Realtek Bluetooth entries.
Reinstall the driver fresh.

2. Driver Details & Installation

The CM390 does not typically ship with a CD driver due to modern obsolescence. Users must download the driver manually.