title: How can a udp broadcast packet be received by wireshark but not socket listener
body: <p>I have a C# app that works on several machines, but for some reason not on another. All are Windows XP. </p>
  
  <p>I simply open up a port and listen:</p>
  
  <pre><code>void Open() 
  {
  var myIpAddress = UdpComm.GetPcIpAddress(target);
  
  listenEndPoint = new IPEndPoint(myIpAddress, RemotePort);
  
  System.Windows.Forms.MessageBox.Show("Creating listener: " + target.ToString() + " - " + listenEndPoint.ToString());
  _client = new UdpClient(listenEndPoint);
  _client.EnableBroadcast = true;
  _client.BeginReceive(ReceiveCallback, null);
  }
  
  public void ReceiveCallback(IAsyncResult ar)
  {
    System.Windows.Forms.MessageBox.Show("Data received");
  }
  </code></pre>
  
  <p>When I run the program, I see that the Open method runs successfully, and that the addresses and ports look correct.</p>
  
  <p>When I look at this on Wireshark I also see that the data being sent from the remote address correctly, but I never see a message box from the callback.</p>
  
  <p>I don't have any errors being thrown. Any ideas of what could cause the data to show up on Wireshark, but not in my app?</p>