Arduino Won't Start

Hey Guys,

For some reason, the Arduino IDE won't start. I recently updated to Catalina 10.15.5, and this problem started. I also used bootcamp assistant to open up Windows, and this problem still occurred. Is anyone else having this problem also?

This was reported on 6/9, and Arduino Support reported today 6/1/2020:

We had a problem on our package_index.json file which caused the current error and it has prevented the IDE to start. Now the package_index.json file has been fixed, but to recover a working installation you must delete once again the package_index.json and restart the IDE as usual.

You can find the package_index.json usually in the following folders:
Windows:

[color=#2b2e2f]remove file C:\Users\YourUsername\AppData\Local\Arduino15\package_index.json
remove folder C:\Users\YourUsername\AppData\Local\Arduino15\cache[/color]

Mac:

[color=#2b2e2f]remove file /Users/YourUsername/Library/Arduino15/package_index.json
remove folder /Users/YourUsername/Library/Arduino15/cache[/color]

Linux:

[color=#2b2e2f]remove file: /home/YourUsername/.arduino15/package_index.json
remove folder /home/YourUsername/.arduino15/cache[/color]

Please note that the problem that prevents the IDE to start has already been fixed for the next releases, that’s the reason why the Nightly/Beta Builds are not affected, and also the reason why we did not detect the problem earlier,