title: Process exists with ExitCode 255
body: <p>[IIS 7.5 / Windows 7 / Visual Studio 2012]</p>
  
  <p>I am trying to have my MVC app run an external command line tool located on the same machine.</p>
  
  <p>I gave execute permissions to IIS_USRS to the whole folder that contains the tool.</p>
  
  <p>I invoke it with:</p>
  
  <pre><code>ProcessStartInfo startInfo = new ProcessStartInfo();  
  startInfo.WindowStyle = ProcessWindowStyle.Normal;  
  startInfo.FileName = myPath;  
  startInfo.Arguments = myArguments;  
  PartialRunProcess = Process.Start(startInfo);  
  </code></pre>
  
  <p>No exceptions (path is right), but the process exists rightaway with ExitCode 255</p>
  
  <p>I can execute the process manually.</p>
  
  <p>What could be the cause ?</p>