Arduino UNO R4 WiFi Not Detected via USB Anymore

Hardware UNO R4 UNO R4 WiFi
1

Hi everyone,

I’m having an issue with my Arduino UNO R4 WiFi board. Yesterday, everything was working fine—I could connect the board to my computer via USB without any issues. However, today, when I plug the board into my computer, it no longer shows up in the Arduino IDE or in the device manager (Windows), and there is no USB connection sound.

Here’s what I’ve tried so far:

•	I used a different USB cable that I know is working.
•	I tested on another computer, but the board is still not detected.
•	I checked the device manager, but there’s no new device under Ports (COM & LPT) or USB.
•	The board still powers on, and the TX/RX lights occasionally blink.
•	I tried entering bootloader mode by double-pressing the reset button, but the board doesn’t show up.

I’m starting to wonder if the USB port on the board is damaged. Is there any way to verify this? Can I still upload sketches using other methods, like Wi-Fi or using an FTDI adapter? Any advice or solutions would be greatly appreciated!

Thanks in advance!

2

Ok, so it sounds like you eliminated both the cable and the computer by testing with another one.

To use WiFi for uploading sketches, requires WiFi and mDNS to be configured and code for OTA updates included in the sketch and working prior to the problem ocurring.

Whether you can still upload a sketch depends on what the problem is. If the MCU is still running then uploading via an FT232RL connected to RX0/TX0 might be feasible although the reset timing is a bit fiddly. Alternatively, you might be able to upload a sketch via the SPI bus using a USBASP programmer or using another Arduino as an ISP programmer:

Arduino as ISP and Arduino Bootloaders | Arduino Documentation

3

Just normal Win device manager stuff. Make sure you close ALL IDE windows, may have to reboot even. Many many issues raised here are about no port.