title: ReflectionTypeLoadException
body: <p>When I try to build My WF project I get this error. I've found that removing <code>System.Activities.Presentation</code> solves this error.
  If I get this error at runtime, I can investigate <code>LoaderExceptions</code> to find out about the root problem.<br></p>
  
  <p>How can do the same when I get this error at compile time?<br>
  Alternatively, does anybody know how to solve this particular problem?</p>
  
  <blockquote>
    <p>Extension 'Microsoft.Activities.Build.Validation.ValidationBuildExtension' threw an exception of type 'System.Reflection.ReflectionTypeLoadException' :  'Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.'.    </p>
  </blockquote>