"full cone test not supported" - what is this?

[Jeremy Nelson]

I've never run across this before - I know what a full cone test failure is, but this is the first time I've ever seen it say "not supported". What does that mean?

 

[Jeremy Nelson]

I finally figured it out on my own. I've experienced reliability issues with the 3CX STUN servers in the past, so I changed the first one to point to Google instead. Apparently the first STUN server is used as part of the firewall checking process. I restored the first STUN server to stun.3cx.com and changed the 3rd to use Google and all is fine now.