title: Restart a completed task
body: <p>I have a Task that run periodically in the background of my application. When I run it for the first time everything is ok and the Task run to end perfectly. But for the second time and after that whenever I use <code>task.Start()</code> it throws an exception: </p>
  
  <blockquote>
    <p>An unhandled exception of type 'System.InvalidOperationException' occurred in mscorlib.dll
    Additional information: Start may not be called on a task that has completed.</p>
  </blockquote>
  
  <p>I am sure that my task function ran to the end.. what should I do to run the task periodically? </p>