[flexcoders] NetConnection.Connect.Failed

[arokyzxc]

I've tried this 
     nc = new NetConnection();
     nc.connect("rtmp:/videodisplay"); 
     nc.addEventListener(NetStatusEvent.NET_STATUS, netStatusHandler);
     nc.addEventListener(SecurityErrorEvent.SECURITY_ERROR,
securityErrorHandler);
and i got "NetConnection.Connect.Failed " message.
I checked that fms was running ,also saw videodisplay _definst_ was
loaded from server admin panel.
i was really confused about it , any suggestion would be appreciate .