My server doesn't seem to want to authenticate on its own anymore. Nobody sees it on the server list until I change a setting like the welcome message through RTB. When I start the server, it shows
Authentication: Connected...
No user/host entry in master server, re-sending authentication request
Authentication: Sending Initial Request...
Dedicated server is now running.
and stops. At this point, nobody can connect or even see the server but me, and only through Query LAN. But once I connect and change a setting, it goes again to "No user/host..." and follows through to "Authentication: SUCCESS", and players can start connecting.
As I have a fairly reliable solution already, I didn't want to make a thread all about this, but I thought it should be known.