Troubleshooting Guide: Restoring the Missing COM Port for Arduino Leonardo

userHead LattePanda 2023-12-18 11:29:07 611 Views1 Replies


The Arduino Leonardo is a microcontroller board based on the ATmega32u4. However, it's not uncommon for users to encounter issues where the COM port for the Arduino Leonardo disappears from the Arduino IDE. This can prevent the successful upload of sketches to the board, hindering the progress of your projects.



Here is a step-by-step guide to restoring the missing COM port for your Arduino Leonardo:


Step 1: Open the Blink Sample Code

1. Launch the Arduino IDE.
2. Navigate to File > Examples > 01.Basics > Blink. This action will open a sample program called "Blink".

Step 2: Prepare to Upload the Code

In the Arduino IDE, locate and click the "Upload" button. This is represented by a right-pointing arrow icon on the toolbar. Clicking this button will initiate the code compilation process.


Step 3: Reset Arduino Leonardo

1. Keep an eye on the bottom status bar of the IDE. 
2. As soon as it displays "Uploading...", promptly press the reset button on the Arduino Leonardo board. This is typically a small button located on the board's surface.
3. After pressing the reset button, the Arduino IDE will attempt to re-recognize the board, and the new COM port should appear in the Ports section of the Tools menu.

If the upload is successful, the LED on the Arduino board will start blinking. You can then select the new port in the Tools menu, and proceed to upload your project code.



If you fail to press the reset button in time during step 3, you may need to repeat this step until successful.


This guide provides a simple and effective solution to restore the missing COM port for the Arduino Leonardo. It's a common issue that can be resolved with a little patience and the right steps.