title: NLog control to an existing RichTextBox Windows Form
body: <p>Below is my NLog configuration, I want to load log into existing RichTextBox called rtMessage in Form1, but NLog will create a new windows with log message loaded into the RichTextBox:</p>
  
  <pre><code> &lt;targets&gt;
      &lt;target xsi:type="RichTextBox" name="m" layout="${longdate}|${level:uppercase=true}|${logger}|${message}" 
              controlName="rtMessage" formName="Form1" /&gt;
    &lt;/targets&gt;
  
    &lt;rules&gt;
      &lt;logger name="*" minlevel="Debug" writeTo="m" /&gt;
    &lt;/rules&gt;
  </code></pre>
  
  <p>Thank you.</p>