Yeah man i’ve had the same thing and it’s been driving me mental. Old server was running Windows 10 on an old Dell Optiplex 960 and I had remote access for over a year then suddenly it’s been disabling itself, working for a minute then saying unavailable. i’ve since built a new server from scratch running on Ubuntu and it’s been a pain to manage. Basically everything is running as it was, but that remote access issue is still prevelant. Dug through the console while clicking ‘retry’ and came across this post, but everything I’ve seen hasn’t helped much. I’ve tried port forwarding, disabling and re-enabling UPnP (that’s what sort of fixed it last time, for a little while at least), turning off ipv6. I’m at my wits end, nothings changed on our local network and it was fine for such a long time and now suddenly remote access doesn’t seem to want to work and i’m out of ideas. Ranting here in the hopes someone comes along and helps us out haha