title: How do I diagnose "Microsoft .NET ClickOnce Launch Utility has stopped working"?
body: <p>We deploy our application using ClickOnce, installed from a file path.  For 24 versions it has been working perfectly - now, on version 25 I get the following error once the application has installed and it launches:</p>
  
  <p><a href="https://i.stack.imgur.com/k5OuD.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/k5OuD.png" alt="alt text"></a>
  </p>
  
  <p>If I test a previous deployment on the same machine, it works.</p>
  
  <p>Where can I even begin to look to find the cause of this error?  I already checked the windows event logs - nothing.</p>
  
  <p><strong>EDIT:</strong> I noticed that while the dialog is displayed, a temporary xml file 'WER561D.tmp.WERInternalMetadata.xml' is generated in my temp folder.  Here is the contents (it might contain clues helpful to those more knowledgeable in this area than I):</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-16"?&gt;
  &lt;WERReportMetadata&gt;
      &lt;OSVersionInformation&gt;
          &lt;WindowsNTVersion&gt;6.1&lt;/WindowsNTVersion&gt;
          &lt;Build&gt;7600 &lt;/Build&gt;
          &lt;Product&gt;(0x4): Windows 7 Enterprise&lt;/Product&gt;
          &lt;Edition&gt;Enterprise&lt;/Edition&gt;
          &lt;BuildString&gt;7600.16385.x86fre.win7_rtm.090713-1255&lt;/BuildString&gt;
          &lt;Revision&gt;1&lt;/Revision&gt;
          &lt;Flavor&gt;Multiprocessor Free&lt;/Flavor&gt;
          &lt;Architecture&gt;X86&lt;/Architecture&gt;
          &lt;LCID&gt;1033&lt;/LCID&gt;
      &lt;/OSVersionInformation&gt;
      &lt;ProblemSignatures&gt;
          &lt;EventType&gt;CLR20r3&lt;/EventType&gt;
          &lt;Parameter0&gt;applaunch.exe&lt;/Parameter0&gt;
          &lt;Parameter1&gt;2.0.50727.4927&lt;/Parameter1&gt;
          &lt;Parameter2&gt;4a275abe&lt;/Parameter2&gt;
          &lt;Parameter3&gt;mscorlib&lt;/Parameter3&gt;
          &lt;Parameter4&gt;2.0.0.0&lt;/Parameter4&gt;
          &lt;Parameter5&gt;4a275af7&lt;/Parameter5&gt;
          &lt;Parameter6&gt;4f3&lt;/Parameter6&gt;
          &lt;Parameter7&gt;0&lt;/Parameter7&gt;
          &lt;Parameter8&gt;System.Security.Security&lt;/Parameter8&gt;
      &lt;/ProblemSignatures&gt;
      &lt;DynamicSignatures&gt;
          &lt;Parameter1&gt;6.1.7600.2.0.0.256.4&lt;/Parameter1&gt;
          &lt;Parameter2&gt;1033&lt;/Parameter2&gt;
      &lt;/DynamicSignatures&gt;
      &lt;SystemInformation&gt;
        -- removed for privacy reasons --
      &lt;/SystemInformation&gt;
  &lt;/WERReportMetadata&gt;
  </code></pre>
  
  <p>Another key point is that I am publishing via Visual Studio, there is no manual manifest editing going on.</p>