This article covers everything: automatic installation, manual driver hunting, fixing the dreaded "Code 10" error, and ensuring your adapter works with Windows 10 and 11. Before clicking "Install," you need to know one critical fact: UGreen does not manufacture Bluetooth chips.
A: That is not a driver issue. That is Bluetooth codec negotiation. The CM390 supports SBC and aptX. Right-click your speaker in "Bluetooth & devices" > Properties > Disable "Handsfree Telephony" to force high-quality audio mode. ugreen bluetooth 50 usb adapter cm390 driver install
It is rare, but you may have a defective unit. UGreen has a solid 18-month warranty. Return it, but there is a 99% chance that following the manual registry fixes above will resurrect your dongle. Frequently Asked Questions (FAQ) Q: Does the CM390 work on Linux or Mac? A: On Linux (Ubuntu/Fedora), the Realtek RTL8761B driver is baked into Kernel 5.7+. It works plug and play . On Mac, it does not work natively due to Apple’s proprietary Bluetooth stack. That is Bluetooth codec negotiation
UGreen is a peripheral assembler. The CM390 typically uses a chipset. While UGreen provides a driver CD (which most modern PCs lack), Microsoft’s generic drivers often fail to initialize this specific chip correctly. It is rare, but you may have a defective unit