title: How do I add an MSBuild .proj file to my solution?
body: <p>Does anyone know how to add a an MSBuild .proj file to my solution?</p>
  
  <p>I was just given existing code from a vendor with a solution that references an MSBuild .proj file as one of its projects.  When I open the solution, the project shows as (unavailable).  It appears that I need to install some sort of project template to get this project to open correctly.  I installed the <a href="http://www.codeplex.com/MSBuildTemplate" rel="nofollow noreferrer">Codeplex MSBuild Template</a>, but this doesn't appear to be it.  </p>
  
  <p>Any ideas?</p>