title: Error while loading project: Attribute Include is unrecognized
body: <p>After merging two branches the Visual Studio has suddenly problems with loading a project.
  When I try to reload, I always get the error</p>
  
  <blockquote>
    <p>The attribute "Include" in element Reference is unrecognized.</p>
  </blockquote>
  
  <p>I have no idea why this happened... how can I get the solution to load the project again?
  Has anyone encountered this error message before and know what I have to look for to find the problem?</p>
  
  <p>The .csproj doesn't really look corrupt on the first sight...</p>
  
  <p>Thanks in advance</p>