title: WCF Protocol Exception
body: <p>I am experiencing real problems with WCF.  For no apparent reason I have started getting the following errors when debugging any WCF service in my solution:</p>
  
  <blockquote>
    <p>ProtocolException Occurred Content
    Type application/soap+xml;
    charset=utf-8 was sent to a service
    expecting text/xml; charset=utf-8. 
    The client and service bindings may be
    mismatched.</p>
  </blockquote>
  
  <p>Clicking continue on the exception window details leads on to a different exception:</p>
  
  <blockquote>
    <p>Could not load file or assembly
    'System.Xml.XmlSerializers,
    Version=4.0.0.0, Culture=neutral,
    PublicKeyToken=b77a5c561934e089' or
    one of its dependencies. The system
    cannot find the file specified.</p>
  </blockquote>
  
  <p>The Disassembly window in Visual Studio also appears when these exceptions occur.</p>
  
  <p>After clicking continue until the exceptions stop the WCF Test Client starts but invoking any of my service methods gives me this exception:</p>
  
  <blockquote>
    <p>PlatformNotSupportedException The
    specified cryptographic algorithm is
    not supported on this platform.</p>
  </blockquote>
  
  <p>I tried to add my existing service to a new blank solution and the errors ceased.  However, after running my service a couple of times, the errors have started again.</p>
  
  <p>I actually have two WCF services in my solution (one a WCF Workflow Service and one a WCF service that exposes data access methods (Entity Framework), a web application and a few other supporting class libraries.  Attempting to run the web application or any service in isolation now gives me the same Protocol Exception.</p>
  
  <p>Any help will be greatly appreciated.  I am using Visual Studio 2010, targeting 4.0 of the .Net Framework.</p>
  
  <p>Thanks</p>