The ListGroups method requests that the server return a
list of available news groups. The OnNewsGroup event will be
fired for each group returned by the server. When the last news group
has been listed by the control, the OnLastGroup event will
fire.
While the the newsgroups are being listed, the client cannot
select a newsgroup or retrieve the contents of a specific article.
The client should store those newsgroups which it wants to retrieve
articles from, and then once all of the newsgroups have been listed,
it can then select each newsgroup and retrieve the available articles
from that group.
A program should use either the ListGroups method or the
GetFirstGroup and GetNextGroup methods, but never in
combination with one another.