Walter Oney said:
The subject says it all. I thought these were managed newsgroups.
Where's the sysop to keep spam and viruses out?
No, these are not managed/moderated newsgroups. They are carried
separately on news servers all over the world, exactly like alt, comp, rec,
sci, talk, etc. Microsoft managed the create messages, but that's only by
convention.
When they started, the microsoft.* groups were hosted at
news.microsoft.com, so you had to log in to their server to fetch them.
Now, they're public.