title: While building a unit test project, VS 2010 cannot find the referenced assembly for testing
body: <p>I'm developing a unit test project (let's say XXX.UnitTest) to test ViewModels in another project (XXX) in my solution. I can add the reference but when I build, an error states that it cannot find that same project (XXX)</p>
  
  <blockquote>
    <p>Error 42  Could not load file or
    assembly 'XXX, Version=1.0.2.66,
    Culture=neutral, PublicKeyToken=null'
    or one of its dependencies. The system
    cannot find the file
    specified.    XXX.UnitTest</p>
  </blockquote>
  
  <ul>
  <li>I did a clean rebuild of all projects in my solution.</li>
  <li>I verified that the assembly with that version number (1.0.2.66) did exist in the path I was referencing.</li>
  <li>I removed and re-added the reference both as a project and through the Browse tab.</li>
  <li>I made sure that the version number was not specified in the csproj file.</li>
  <li>I verified the referenced assembly with Dependency Walker.</li>
  <li>I verified that both projects were targeting the x86 platform. (As suggested here <a href="https://stackoverflow.com/questions/2263580/tips-to-help-debug-could-not-load-file-or-assembly-x-or-one-of-its-dependencies">Tips to help debug &quot;Could not load file or assembly X or one of its dependencies&quot;</a>)</li>
  </ul>
  
  <p>Does anyone know what else can cause this problem?</p>