I have not used Arduino IDE since moved back to Windows 10 as my primary OS. Recently I wanted to do some coding with my Arduino Due board. As soon as I opened the board manager, I was “welcomed” by a nasty error. Below you can find the full text of the error.
"Error downloading http://downloads.arduino.cc/packages/package_index.json java.lang.RuntimeException: java.lang.Exception: Error downloading http://downloads.arduino.cc/packages/package_index.json at cc.arduino.contributions.packages.ui.ContributionManagerUI.lambda$onUpdatePressed$1(ContributionManagerUI.java:150) at java.lang.Thread.run(Thread.java:748) Caused by: java.lang.Exception: Error downloading http://downloads.
As it’s said, once you solve problem #1, problem #2 gets a promotion. So, after fixing the problem with downloading package_index.json file, Arduino IDE immediately started complaining about file integrity.
To be honest, I’m not sure why this mess has happened but this is a really annoying thing. Fortunately, the problem can be solved easily if you have correct files.
So, let’s get back to the problem. The problem happens when you open the board manager in Arduino IDE.