Was recently coding in the Arduino IDE program started crashing well initializing after poking around I found the configuration files C:\Users\Your User Name\AppData\Local\Arduino15 delete the files in this folder you can keep preferences.txt the program will start again normally fastest way to open the folder is to paste %USERPROFILE%\AppData\Local\Arduino15 Into the location bar of an explorer window
The bug was reported and fixed https://github.com/arduino/Arduino/is... if you ran arduino on June 9th10th 2020 you will have to remove the files so Arduino will start again