COM4 not available, reinstalled Arduino


Not sure if this has been resolved or another forum post but I’m having trouble finding the port to my board. I have followed the walk through for set up twice, reinstalled Arduino and still is greyed out for me to select. Also, the tutorial says it should look for COM 3 anyway?

When I first installed Arduino, I updated everything to newest versions (hence the latter uninstall and reinstall to follow the tutorial) but still wasn’t able to find it. The USB port drivers have been installed probably three times now, is there a way to verify that in my Device Manager?

Let me know what I can do over here or check on …



Since no one else has replied I’ll jump in as I’ve had my share of USB-serial problems on Windows in the past.

Here are some starter questions for you:

  1. What version of Windows are you on?
  2. What do you see when you open up Device Manager? You should see an entry for the Serial device when you have the ESP board plugged in and if the serial driver has loaded properly for it. If you don’t, check under system devices and see if you see any devices that might be related to it. Screenshots would help.
  3. It’s possible the USB cable you’re using is not passing the data/power or the board has a problem. Have you tried swapping the microUSB cable with another known good cable that allows for power and data transfer?


For an easy reply in number for as you have you questions, here we go

  1. Windows 10
  2. I was able to get a NodeMCU last week and seems to be able to find the port just fine…That was the only difference was the board. The USB, breadboard and components all came with the builder kit. I’ll do some testing for the Adafruit later, hopefully not a defunct one :\
  3. The USB i got with the Adafruit huzzah is the same im using with the NodeMCU and working fine for that. I did swap it out and no difference…

Updates later :slight_smile: