Frustrated, she opened her laptop, navigated to Device Manager, and found the culprit: a yellow exclamation mark beside “Unknown USB Device.”
Evan found the tiny UGREEN Bluetooth 5.0 USB adapter tucked under a stack of manuals like a secret. The silver dongle was no bigger than his thumb, but the label—CM390—felt like the name of a ship about to sail. ugreen bluetooth 50 usb adapter cm390 driver install
A: USB port power saving. Go to Power Options → Change plan settings → Change advanced power settings → USB settings → USB selective suspend setting → Disable. Frustrated, she opened her laptop, navigated to Device