Bill
That would likely be because you've only added the MS news servers, which
carry only the MS news groups.
If you want a wider range of newgroups, and there certainly is a vastly
wider range in the tens of thousands - you'll need to find another News
provider. Many ISPs are terminating their UseNet services. Some claim
there is little demand, but I suspect that it's because they fear legal
liability for things that can be found on the servers they have to hold.
So, look at 3rd party servers like GigaNews, Supernews, etc. It's a few
dollars a month, I think I pay perhaps six, but I find it works out much
better than when my SP mishandled it.
You can also find free servers. These come and go all the time, few allow
posting, retention is limited. Anonymous posting services suffer from
similar problems.
HTH
-pk