I've plugged my ELEGOO Uno R3 into a USB port on my computer with a USB cable. However, neither Arduino IDE nor my computer can see the device. When the Uno is connected, it shows no connected devices. The problem is not the USB port or cable; both work with the Arduino Mega 2560 and the Adafruit Metro 328.
The Uno still receives power from the computer; the green LED is on when the Uno is connected. Why can't the computer see the Arduino?
