title: What is the correct way of using the Guid type in a XSD file?
body: <p>I have a .xsd file which I use to generate code with the xsd.exe tool from Visual Studio.
  Some class members are Guids and the xsd.exe tool gives 2 warnings:</p>
  
  <p>Namespace '<a href="http://microsoft.com/wsdl/types/" rel="noreferrer">http://microsoft.com/wsdl/types/</a>' is not available to be referenced in this schema.
  Type '<a href="http://microsoft.com/wsdl/types/:guid" rel="noreferrer">http://microsoft.com/wsdl/types/:guid</a>' is not declared.</p>
  
  <p>The Guid type is recognized because the generated C# file is valid and works.
  Anyone knows how to get rid of those warnings?</p>
  
  <p>What is the correct syntax for the XSD to be validated AND class members being generated as System.Guid?</p>