Another user pointed out that when they set options to IPv6 preferred, they could not post in the channels. I set my system to IPv6 preferred and can confirm that posting fails.

But is it fopnu or is it possible my system is not configured properly for IPv6?  How to determine, how to test?

When I do ipconfig /all the results for my wifi adapter show an IPv6 IP, so I assume it is active.

With my connections set to IPv4 I note that all IPv6 connections attempts fail.

Then I also see this on the event log:

[6:53:25 PM]  NAT-PMP mapping UDP port * on gateway 192.168.*> socket error waiting for reply: Timed out (50434)
[6:53:26 PM]  UPNP mapping UDP port * on gateway 192.168.* > command failed with error 402 Invalid Args
[6:53:26 PM]  Mapping UDP port * on gateway 192.168.* will be retried every 5 minutes

I checked my modem/router settings.
UPN is enabled
port forwarding is set for the port I have configured in fopnu for UDP only, not TCP

I note from the log it says error 402, Invalid Args. That sounds like a fopnu issue to me. Is that correct?

I have both a working IPv6 connection and use IPv6 Preferred and do not have this problem.

here is a picture of my event logs
fopnu:file:cvo6rdltuf57hekh7bnm7udsywuq3643wb6lkelvkdx2lw5vv6xv6niaaaaaaaaa/Event%20Logs.png

and here is a picture of my Network settings
fopnu:file:625jx6xqynqzlslkvz74bokqwuptbj4njdwmnqckfdg3uvz27q22slaaaaaaaaaa/Network%20Settings.png

Many VPNs don't support IPv6, do it's better to use IPv4 anyway.

I did a little testing and determined IPv6 was not functioning, by an online test.

It may be that my ISP doesn't support it as I think i have configured things in windows, my router and fopnu properly.

Will try to test ISP more later.

If you are using a VPN most block IPV6 for security reasons.

Back on this after the release of SSS

SSS reports: [2:47:24 PM]  DDNS IPv6 update error: Host not found (49410) at https://freemyip.com/update?token=

on fopnu, Network/IPv6 Peers, there are no OK entries, all are "Missed Last ## Pings"

Called ISP and Customer Service replied?  "IPv6? What is that?"  then "Oh. That sounds like a Tech Support issue."  Tech support wasn't sure. Said my modem is IPv6 capable but they didn't think it was supported yet in my service office.

Ok, the ISP doesn't provide IPv6 yet...but ...

On Tixati (set IPv4 Preferred), on DHT/IPv6 Node Table,  I am showing many IPv6 connections are "OK Expires in #:##".  Many other connections report "Uncertain Expires in #:##"

So I am confused. If my ISP doesn't support IPv6 at this location, how does Tixati have several OK IPv6 nodes connected?