title: Why is Flash demanding a crossdomain.xml file when the .swf and http target are both on localhost?
body: <p>I've got a small client/server test application where I have a Flex app that makes an HTTP request of a server app.  The server app is a script running on my local machine, listening on port 8001.  The client is a swf that I am running locally, and uses <code>mx.rpc.http.HTTPService</code> to make the page request.</p>
  
  <p>The HTTPService is being set up as per below:</p>
  
  <pre><code>_HttpService = new HTTPService();
  _HttpService.url = "http://localhost:8001";
  _HttpService.contentType = "text/xml";
  </code></pre>
  
  <p>When I make a basic page request, my server app is first receiving a <code>"GET /crossdomain.xml HTTP/1.1"</code> request, which is failing since I don't have a crossdomain.xml file in place.  The reason I don't have one in place is because this is all happening on my local machine (for now) and I shouldn't need one (I don't think).</p>
  
  <p>I definitely had this code working before without a crossdomain.xml when I was using Flex 3.x.  I thought I had it working with Flex 4 as well.  Now I'm using Flex 4.5.  Is there an issue here, possibly due to security policy changes?</p>
  
  <p><strong>With all of this happening on localhost, why is the Flash player requesting a crossdomain.xml file?</strong></p>
  
  <p>In case it helps, the specific fault my AsyncResponder is getting back is:</p>
  
  <pre><code>[FaultEvent fault=[RPC Fault faultString="Security error accessing url" faultCode="Channel.Security.Error" faultDetail="Destination: DefaultHTTP"] messageId="F43DCBFF-E99A-99CC-57D8-535C13C7CD48" type="fault" bubbles=false cancelable=true eventPhase=2]
  </code></pre>