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.

2 Answers 2


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
    Commented Apr 14, 2016 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
    Commented Jun 12, 2016 at 19:46

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


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