I have been using version 1.6.5 version if the Arduino IDE for ESP8266 for quite a while. It works great.
I decided I wanted to try the new serial plotter so I installed version 1.8.3. Now, I can’t compile any sketch for ESP8266. I can select the module from the board list, but when I try to compile, I get the following error messages:
Board nodemcuv2 (platform esp8266, package esp8266) is unknown
Error compiling for board NodeMCU 1.0 (ESP-12E Module).
I tried a couple of other boards in the series with the same result.
I restarted the computer before compiling the sketch without any success.
I’m running Windows 10
That’s not a typo, it does say nodemcuv2 in the error message. I wonder if that v2 is a clue to the problem.