The Arduino SW, under Tools, identifies my Uno as COM Port 3. However, COM Port 3 on my computer is in use by a chip set. My computer assigned COM Port 4 to my Arduino Uno.

Can I reassign my Uno to COM Port 4?

Edit: This question also applies to people who don't have administrative privileges. They do not have privileges to change the port via Windows Device Manager.


If the Arduino IDE identified your Uno as COM Port 3, your computer most likely has already assigned COM Port 3 to your Uno. You can double check the port assignment in Device manager > Ports.

  • The issue is that I am not an admin and do not have the ability to re-assign ports on the computer. Therefore, I would like to Re-assign the port that Arduino is requesting. It can't be that hard.
    – brianlloyd
    Apr 14 '16 at 16:27
  • This is not an answer. You can reassign the com port via the device manager... Assuming you are on a Windows PC
    – PhillyNJ
    Jun 12 '16 at 19:46

You can change your COM Port number for a device by following these instructions:


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