I'm trying to setup Authpoint for the SSL VPN but it isn't working.
There are a few different places where it could be failing. When the user authenticates to the VPN the Firebox passes the credentials to the Authpoint gateway using RADIUS, which passes them onto the cloud over port 443.
Check the gateway RADIUS logs at C:\Program Files (x86)\WatchGuard\Authpoint RADIUS\logs\radius.application.log for port conflicts or other connection errors, if you don't see any logs the Windows firewall might be blocking the connection.
Check the WatchGuard Cloud dashboard as well, the Logs and Events area will log any login attempts that make it to the cloud. If it shows unauthorized it could be an issue with the access policy you've setup for the RADIUS client in the Authpoint group, or double-check the RADIUS shared secret.