Comment 13 for bug 1945030

The solution I found is with Network-Manager settings found in the file: /etc/networkmanager/networkmanager.conf.

Change setting under heading ifupdown from managed=true to managed=false; restart the system and discover will refresh the cache and you will no longer get the message: "cannot refresh the cache whilst offline".

Simple fix!!! Hope it works for everyone as it has for me. Mike