title: The HTTP request is unauthorized with client authentication scheme 'Ntlm'
body: <p>While calling a web service I get the following error:</p>
  
  <blockquote>
    <p>The HTTP request is unauthorized with client authentication scheme 'NTLM'. The authentication header received from the server was 'NTLM'. The HTTP request is unauthorized with client authentication scheme 'NTLM'. The authentication header received from the server was 'NTLM'.</p>
  </blockquote>
  
  <p>I have a Silverlight 4 application that calls a WCF web service, both on my IIS (7).
  my WCF web service calls another ASMX web service, installed on a different web server, using NTLM (Windows Authentication).
  Both servers, mine and the one hosting the ASMX web service are in the same domain.</p>
  
  <p>When the Silverlight client opens the application from the server using <code>http://localhost/MySiteName</code> everything works fine. But when the Silverlight client opens the application from a different client, which is not the server but still in the same domain, using <code>http://MyServerName/MySiteName</code> then I get the error.</p>
  
  <p>Windows Authentication is enabled in my IIS.
  Anonymous Authentication is disabled in my IIS.</p>
  
  <p>Binding configuration for calling my WCF web service is:</p>
  
  <pre><code>    &lt;binding name="winAuthBasicHttpBinding"&gt;
        &lt;security mode="TransportCredentialOnly"&gt;
          &lt;transport clientCredentialType="Windows" /&gt;
        &lt;/security&gt;
      &lt;/binding&gt;
  </code></pre>
  
  <p>Binding configuration for calling the ASMX web service is:</p>
  
  <pre><code>    &lt;binding name="ClNtlmBinding"&gt;
        &lt;security mode="TransportCredentialOnly"&gt;
          &lt;transport clientCredentialType="Ntlm" /&gt;
        &lt;/security&gt;
      &lt;/binding&gt;
  </code></pre>