When I clicked on Windows Update, the site came on but then did nothing, i.e., did not analyze my computer and identify which updates I needed.
I could download stuff from the Internet but NOT from the Windows Update site. I wasn't going to go running around guessing which Windows updates I might need, and apparently Windows Update would not let me download stuff anyway without the Windows Update analysis of what my computer needed.
I couldn't figure out the fix on my own, including browsing the Microsoft help and newsgroup areas. So I wrote an e-mail outlining my problem and the Microsoft response was excellent. Friendly tone, clear writing, and successful fix.