I have a service registered for shutdown events (.Net 3.5):

   public ServiceName()
    {
      InitializeComponent();
      base.CanHandleSessionChangeEvent = true;
      base.CanHandlePowerEvent = true;
      base.CanShutdown = true;
    }

   protected override void OnShutdown()
    {
      try
      {
        if (Program.Debug2Eventlog == true)
        {
          WriteEventEntry(
              "Computer is shutting down.",
              EventLogEntryType.Information, 0, 3);
        }
      }
      catch
      {}
       base.OnShutdown();
    }

Windows 7 logs the event just fine, but XP doesn't. Am I missing something?