How to add a serial port for instance COMX?

We are trying to add port COMX under tools serial port. No COM port is displayed. how can we add ports under serial port??


COM port is added automatically when the board is connected to the computer with a usb data cable. A driver for the usb-serial chip used on the board, may need to be installed manually.

hello greetings thank you for your advice could you please explain to me a little bit more how to install it, I'm having issues programming a arduino robotic starter kit.

Windows, since Windows 7 will automatically install the device driver for the UART chip as soon as it sees it. Like when you plug it into the USB port.

Open the device manager then expand "Ports (COM & LPT)". When you plug in the Arduino into a USB port you should see a new com port. If not, are you using a genuine Arduino? (You didn't say which Arduino).

I'm using UNO MAX. But now I found this information on th OSEPP website and is telling me that the USB to serial is now done with the ubiquitouss CH340G requiring fewer driver installs. I would really appreciate if someone would please advice me how to proceed, is a basic robotic kit

Found the issue, I really appreciate your advice guys you led me to a conclution, my PC did not have the right drivers so I just used my wife's laptop MAC and it worked. I'm a new guy starting to dicover this amazing world of electronics.

See the CH340 section.

Could you take a few moments to Learn How To Use The Forum

It will help you get the best out of the forum in the future.

  • Your OS and version can be valuable information, please include it along with extra security you are using.
  • Always list the version of the IDE you are using and the board version if applicable.
  • Use quote or add error messages as an attachment NOT a picture.
  • How to insert an image into your post. ( Thanks @Robin2 )
  • Add your sketch where applicable but please use CODE TAGS ( </> )
  • Add a SCHEMATIC were needed even if it is hand drawn
  • Add working links to any specific hardware as needed (NOT links to similar items)
  • Remember that the people trying to help cannot see your problem so give as much information as you can


  • Ensure you have FULLY inserted the USB cables.
  • Check you have a COMMON GROUND where required. ( Thanks @Perry)
  • Where possible use USB 2.0 ports or a USB 2.0 POWERED HUB to rule out USB 3.0 issues.
  • Try other computers where possible.
  • Try other USB leads where possible.
  • You may not have the correct driver installed. CH340/341 or CP2102 or FT232 VCP Drivers - FTDI
  • There may be a problem with the board check or remove your wiring first.
  • Remove any items connected to pins 0 and 1.


  • Close any other serial programs before opening the IDE.
  • Ensure you turn off any additional security / antivirus just to test.
  • There may be a problem with the PC try RESTARTING it.
  • You may be selecting the wrong COM port.
  • Avoid cloud/network based installations where possible OR ensure your Network/Cloud software is RUNNING.
  • Clear your browsers CACHE.
  • Close the IDE before using any other serial programs.
  • Preferably install IDE’s as ADMINISTRATOR or your OS equivalent


  • CH340/341 based clones do not report useful information to the “get board info” button.
  • NANO (Old Types) some require you to use the OLD BOOTLOADER option.
  • NANO (ALL Types) See the specific sections lower in the forum.
  • NANO (NEW Types) Install your board CORE’s.
  • Unless using EXTERNAL PROGRAMMERS please leave the IDE selection at default “AVRISP mkII”.
  • Boards using a MICRO usb connector need a cable that is both DATA and CHARGE. Many are CHARGE ONLY.

CREATE editor install locations.

  • On macOs ~/Applications/ArduinoCreateAgent-1.1/
  • On Linux ~/ArduinoCreateAgent-1.1/config.ini
  • On Windows C:\Users[your user]\AppData\Roaming\ArduinoCreateAgent-1.1

Performing the above actions may help resolve your problem without further help.
Language problem ?
Try a language closer to your native language:

Thanks to all those who helped and added to this list.

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