My wsus has not been working for about 2 months now. Don't know what i did to mess it up.
i reinstalled the service and the administration console. the computers in our domain show up fine in the wsus console and they show up in the same groups that they did before.
the group policy looks fine to me.
in gpmc the scope is set to my domain level. the security filtering is set to authenticated users.
one interesting thing
after reading another article i saw that my client computers were supposed to have this key in the registry.