title: Fail to open excel file using Process.Start() in .Net4.0
body: <p>Recently an old project of .Net 1.1 is migrating to .Net4.0. The project is using the following method to open excel file:</p>
  
  <pre><code>Process process = new Process();
  
  try
  {
    process.StartInfo.FileName = marco_file;
    process.Start();
  }
  catch(Exception)
  {
  }
  finally
  {
    process.Close();
  }
  </code></pre>
  
  <p>And the marco_file is the path of excel file with macros, like "C:\project\test.xls"
  The macro in it will run immediately when the excel file open.</p>
  
  <p>In .Net1.1 both the codes and the macro runs well. In .Net4, the codes runs without exceptions. But the macro didn't work.</p>
  
  <p>Why the macro in the excel file didn't run?</p>
  
  <p>My environment is Win7 64bit. Office 2010 64bit. IIS 7.5</p>
  
  <p>Thanks</p>
  
  <p>When I change to the following codes and run the debug mode</p>
  
  <pre><code>process.StartInfo.FileName = marco_file;
  if (process.Start())
  {
      Debug.WriteLine("--&gt;start ");
  }
  else
  {
      Debug.WriteLine("--&gt;failed ");
  }
  </code></pre>
  
  <p>The result is that it goes into the else block, which means the process fails to start.</p>
  
  <p>Any one knows why?</p>