title: Tests Disappeared in Visual Studio 2013
body: <p>All of my unit tests have disappeared suddenly in Visual Studio 2013 and I can not seem to get them to be discovered in the Test Explorer.</p>
  
  <p>We use visual studio 2010 as our primary environment.  I have Visual Studio 2013 Express Desktop installed as my editor of choice, work in it, then do final build/check-in with 2010.  Everything works fine in 2010.  But 2013 express will not discover tests anymore.  It used to, then in the middle of working a change it stopped.  These are mstest tests.</p>
  
  <p>I get the following Tests output:</p>
  
  <pre><code>------ Discover test started ------
  TestTypes\13cdc9d9-ddb5-4fa4-a97d-d965ccfc6d4b could not be loaded because the TIP could not be instantiated for the following reason(s): System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.VisualStudio.QualityTools.Tips.UnitTest.Tip, Version=12.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
  File name: 'Microsoft.VisualStudio.QualityTools.Tips.UnitTest.Tip, Version=12.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
     at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMarkHandle stackMark, IntPtr pPrivHostBinder, Boolean loadTypeFromPartialName, ObjectHandleOnStack type)
     at System.RuntimeTypeHandle.GetTypeByName(String name, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark&amp; stackMark, IntPtr pPrivHostBinder, Boolean loadTypeFromPartialName)
     at System.RuntimeType.GetType(String typeName, Boolean throwOnError, Boolean ignoreCase, Boolean reflectionOnly, StackCrawlMark&amp; stackMark)
     at System.Type.GetType(String typeName, Boolean throwOnError)
     at Microsoft.VisualStudio.TestTools.TestManagement.TipDelayLoader.LoadTip()
  
  WRN: Assembly binding logging is turned OFF.
  To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
  Note: There is some performance penalty associated with assembly bind failure logging.
  To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].
  
  ========== Discover test finished: 0 found (0:00:00.1640164) ==========
  </code></pre>
  
  <p>Steps attempted to fix:</p>
  
  <ul>
  <li>Checked out fresh copy of source from the repository</li>
  <li>Verify other developers do not have this problem (their 2013 installs find tests)</li>
  <li>Repair 2013</li>
  <li>Remove 2013, reboot, install 2013</li>
  <li>Created new WPF project and added test (that test discovered, but problem not solved)</li>
  </ul>
  
  <p>Any suggestions would be appreciated.  My next step is to wipe the system, but that will be painful.</p>