See this page
URL:MailToProtocol and see if it fits your problem.
BTW, Outlook does not support newsgroup reading. Outlook 2000 uses a news only version of Outlook Express to handle news reading, which you launch from View>Go To>News.
If that does not work, try setting up your Newsgroup accounts in Outlook Express first.
You might find the following articles useful:
OL2000: Why Outlook 2000 Requires Outlook Express
Q230076
OL2000: Installing and Using the Outlook Newsreader
Q195879
If you are interested in putting a shortcut on your desktop to access the newsreader.
Create a shortcut on your desktop and put this in as the
Target entry:
"X:\Program Files\Outlook Express\MSIMN.EXE" /outnews
Where
X is the drive letter where your program resides. Include the quotes and change the path if not correct.
This thread continues here:
http://forums.techguy.org/archive-web-email/23491-resolved-outlook-2000-addresses-depends.html
[Edited by EAFiedler on 04-04-2001 at 04:24 PM]