title: csc error cs0006 metadata file could not be found building a .net 3.5 application with TFS 2012
body: <p>We are upgrading from TFS 2008 to TFS 2012.  Majority of our applications are .net 3.5 applications.<br>
  We have setup a TFS 2012 environment and went through migration process. When we attempt to build our .net 3.5 applications we are getting the error:</p>
  
  <pre><code>csc error cs0006 metadata file could not be found........
  </code></pre>
  
  <p>If we take a .net 3.5 application, upgrade it to .net 4.x, then run the build again, it works just fine.</p>
  
  <p>I cannot upgrade every single application I have during this migration.  Is there something I might be missing either in the migration or on my build box to support 3.5?</p>
  
  <p>I have VS 2008, 2010, 2012 installed on my build server. I have .net frameworks installed, etc.  </p>
  
  <p>Any assistance is helpful.</p>