My computer cant find ""

Just tried it on my Surface Pro running Windows 10 Pro, after updating the Arduino IDE to 1.8.19. Got a similar error tring to install the Sparkfun Apollo3 boards:

“Error downloading …

Same error regardless of version number, 1.2.1 (as in instructions) or 2.2.1 (latest).

This is very strange. Why same error on 3 different computers on same network? I looked at the preferences.txt file shown under the “Additional Boards Manager URLs:” line. It shows “boardsmanager.additional.urls=” without the URL shown in the box above. ( … index.json ) Is this normal? Should that URL be written into the preferences file?