When your server connects to the On-Air service an access check is performed by the On-Air service to check that the server can be accessed correctly. The On-Air service connects to the port number defined in the server's network pane (this port is usually 7999). If this check fails a warning icon is displayed; the reason why the check fails is most probably a firewall blocking the server's port. If the On-Air service cannot connect then the console will not be able to connect.
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