title: Appending a string adds first line twice
body: <p>I´m generating a list of product orders, which then is sent by mail to an employee.
  The mail body (html) contains a formatted string of quantity and article number.
  The string is generated like this:</p>
  
  <pre><code>                if (order.AssemblyOrderID == assemblyOrderIDs[assemblyOrderIDs.Count - 1])
                  {
                      orderBody += order.OrderQuantity + "x " + order.Article.Article_Number + "&lt;br /&gt;";
  
                      objMM.Body += orderBody;
                  }   
  </code></pre>
  
  <p>Problem:
  The first line of this string is generated twice.
  I stepped through my code but according to the debugger it is working as expected.</p>
  
  <p>The mail instead shows a string like this:</p>
  
  <p>2x 12345<br> 
  2x 12345<br>
  9x 99999<br>
  <br>
  Any suggestions?</p>