NLog RichTextBox error when loaded
===

Below is my NLog configuration, when I load the logger `private static Logger logger = LogManager.GetCurrentClassLogger();` in my form, I got an error:

     <targets>
        <target xsi:type="RichTextBox" name="m" layout="${longdate}|${level:uppercase=true}|${logger}|${message}" 
                controlName="rtMessage" form="Form1" />
      </targets>
    
      <rules>
        <logger name="*" minlevel="Debug" writeTo="m" />
      </rules>

Thank you.