I'm using GRASS GIS Ver 7.2.2. When I enter command mode and type "g.extension r.hypso" I get the message:
Downloading precompiled GRASS Addons ... ERROR: Extension not found
This happens with all of the extensions I've tried to download (attempts over a 3-day period). I re-installed GRASS with no luck.
I am able to query the server's directories and get a list its contents but not successfully add an Addon to GRASS GIS.