NAV message at Windows shutdown

Using Win XP SP3.  Since installing  liveupdate of NAV11 18.6.0.29 I have seen a new phenomenon occur occasionally when I end a session and shut down my computer.    As Windows is shutting down, a popup occurs like Windows is ending a process and there is a slight delay in shutdown.   It's only a handful of seconds (perhaps 3-5 seconds),. and then Windows finishes shutting down.  It's not the same message box that Windows use when it asks you if you want to manually end a task and shutdown.  In fact, the message box hasn't persisted long enough for me to write down the complete name of the process, but it's something like

 

sym_avpapp_window_name

 

That's probably not exactly correct, and may even be longer.   It appears in the title bar of the little message window.   I'm trying to pay attention quickly when it happens so that I can write down the whole name correctly, but it's kind of an unusual name with underscores, and it's very intermittent.   I was just curious if anyone else has noticed this occasional pop up message as Windows XP shuts down, and if there's any significance to it.  Thanks!