Windows Update always show no updates available

When I "scan for updates", it shows 0 for Critical, 0 for drivers, and the "Windows" one is greyed out (I can't choose it) and the scan shows 100% complete (so I assume it's done). After a couple of months, there is no way that there are no updates for me to download. I'm the administrator so there is no permission issue. Everything else seems to work (including Office updates).

Anyone have any ideas?

Thanks,
Norm.