terraria error

System.Net.Sockets.SocketException (0x80004005): Only one usage of each socket address (protocol/network address/port) is normally permitted
	at System.Net.Sockets.Socket.DoBind(EndPoint endPointSnapshot, SocketAddress socketAddress)
	at System.Net.Sockets.Socket.Bind(EndPoint localED)
	at System.Net.Sockets.TcpListener.Start(Int32 backlog)
	at Terraria.Netplay.ServerLoop(Object threadContext)