Home Assistant doesn´t reach Arduino

Hi everyone.
I´m trying to connect na Arduino board to the Home Assistant.
I´m using code like showing in Home Assistant page.
The code looks like:

arduino:
  port: /dev/ttyS2

So, it´s returning this error message:
Your port /dev/ttyS2 is not accessible

Someone coudl help me solve this…

Thanks

Edit: Home Assistant is installed in Windows 10, and maybe should be some configuration on Win10, but I don´t know how to do.

I think I solve the problem.
The code in the HA page is for Linux based system.
I just try:
arduino:
port: COM3
And it´s work.