VS 2008 Web Browser History

Hi, I have entered this code into my web browser's DocumentCompleted event.

"Listbox1.items.add(webbrowser1.url.tostring)
My.settings.history.add(webbrowser1.url.tostring)"

Also, the history settings is set to a specialized string collection.


So when I run the program, why does the history link come up not only once like it is supposed to, but three-six times? Thanks!