title: "Error while trying to run project: Unable to start program". Can run program only once. Then VS needs restart
body: <p>I'm running my .NET 4.0 (C#) project in debug mode after I start VS2013. It runs just fine.</p>
  
  <p>The second time I start it from VS, I get the Dialog box that says <code>"Error while trying to run project: Unable to start program C:\path\to\file.exe"</code> </p>
  
  <p>The process is still alive in the Taskmanager when I dismiss the dialog box.
  From Windows Explorer, I can run the program just fine. And after closing it, the process is gone too from the Task Manager.</p>
  
  <p>A rebuild doesn't help.
  Is this a common problem with a known solution?</p>