title: After opening project in Visual Studio, Blend stopped rendering the preview
body: <p>I have a problem with Visual Studio 2010. When I open any projects created in Blend 4, and simply save it (no modification made), Blend stop rendering preview at the design time.</p>
  
  <p>I am using Expression Blend 4.
  Preview in Visual Studio 2010 is rendered.</p>
  
  <p>So I think, there is some information in the project file, which is added by Visual Studio which prevents Blend from rendering controls. Any ideas of why is that happening?</p>