I have tried deleting the Arduino15 folder and then restarting Arduino IDE, but the error persists.
I have searched the forum and found several posts on this problem, but there is not much advice on possible solution. One post suggests I launch a CDN refresh, but I have no idea how to do this.
"flash_999" has a post on Mar 29 2020 which says:
"Without making any further changes, the problem went away. This could indicate the issue might have been a transient network caching problem."
So, should I just wait for the problem to go away; might be a long wait ?
I'll be grateful for any advice; many thanks. Ken.
My PC is using Windows 10 Home, version 1903
Arduino IDE is version 1.8.9
or do you see something else. The reason I ask is because I have seen one or two reports where someone was having the problem of the network security system actually replacing the downloaded files with some HTML, I guess in an attempt to be helpful, but actually doing just the opposite.
Yes, I have successfully downloaded and opened the json file, and it starts exactly as your code snippet, including the checksum which is same as in yours.