Unfortunately, Windows shows "Unknown" devices in the Device Manager differently based on the version of the OS.
The easiest way to tell which unknown device to install the drivers is to follow these steps:
- Make sure the Arduino is disconnected from the system.
- Open the Device Manger by following the steps you already indicated earlier.
- Connect the Arduino to the system, watch the Device Manger. You should see a new device show up in the list. It might show up under Uknown devices or something like that.
- Once you have identified which device is the Arduino in the list, follow the remaining steps to install the driver
- “Right click on the "Arduino UNO (COmxx)" port and choose the "Update Driver Software" option.”
- “ Next, choose the "Browse my computer for Driver software" option.”
- “Finally, navigate to and select the Uno's driver file, named "ArduinoUNO.inf", located in the "Drivers" folder of the Arduino Software download (not the "FTDI USB Drivers" sub-directory).”