If the selected board in Arduino Web Editor could not be detected, the board selector will display a red cross.
Learn how to troubleshoot possible issues when connecting a board to the Web Editor.
Note: If you are using a Chromebook, make sure to install the Arduino Cloud for Chromebook app.
Make sure to select the connected board in the board selector. Sometimes the Web Editor will show the red cross icon and the name of a board that has been previously connected to the Web Editor:
Check that your device is powered. One or more more LEDs should be lit.
Ensure you’ve connected your board with a working data USB cable.
If you haven’t done so already, install Arduino Create Agent.
Check if HTTPS certificates have been installed:
- Open the Arduino Create Agent menu (Look for the icon in the top-right of the menu bar for macOS and Linux or in the bottom-right of the taskbar within the system tray, for Windows).
- If the Generate and Install HTTPS Certificates option is available, click it. If it’s disabled, the certificates are already installed.
- Enter password if prompted.
- Refresh the browser window.
Classic Nano boards and boards with generic USB chips
Classic Nano boards and some clone boards with generic USB chips will show up as “Board” in the board selector. When selecting a “Board” port you will be prompted to select the board type manually.