Una vez desconectado el socket, sólo puede aceptar de nuevo de manera asincrónica. Se debe llamar a BeginAccept en un subproceso que no saldrá hasta que la operación se haya completado.
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English version
Once the socket has been disconnected, you can only accept again asynchronously. BeginAccept must be called on a thread that won't exit until the operation has been completed.