Arduino IDE 1.8.6 not starting.
The cause of the problem is that you have a corrupted library index file. The solution is to delete the file, which will force the Arduino IDE to download a (hopefully) uncorrupted fresh version from the Internet:
- Open the C:\Users\JK\AppData\Local\Arduino15 folder
- Delete the file library_index.json
- Try starting the Arduino IDE again
For anyone encountering this problem who is using an operating system other than Windows, the location of library_index.json is different:
On Linux:
/home/{username}/.arduino15 (a.k.a. ~/.arduino15)
On macOS:
/Users/{username}/Library/Arduino15
If using the Arduino IDE in portable mode:
{Arduino IDE installation folder}/portable
The issue of a corrupted library index file preventing the Arduino IDE from starting has been reported to the Arduino developers and they are already working on a fix:
https://github.com/arduino/Arduino/issues/7937