The ListArticles method requests that the server return a
          list of news articles in the specified range for the current
          newsgroup. The OnNewsArticle event will be fired for each
          article returned by the server. When the last news article has been
          listed, the OnLastArticle event will be fired.
          While the articles in the newsgroup are being listed, the client
          cannot retrieve the contents of a specific article. For example, the
          GetArticle method cannot be called while inside the
          OnNewsArticle event. The client should store those articles
          which it wants to retrieve in an array, and then once all of the
          articles have been listed, it can begin calling GetArticle for
          each article number to retrieve the article text.
          A program should use either the ListArticles method or the
          GetFirstArticle and GetNextArticle methods, but never in 
          combination with one another.