I've got a machine that can't enumerate the Local Administrators group. The users are there, as I can add to it and see the group membership in the users' profile, but nothing shows up when looking at the Local Admins group. I can also try and add a user that I know is already there, and it won't let me, telling me that the user is already a member. I've tried reinstalling SP4, and joining and unjoining a domain, but nothing seems to help. Does anyone have any idea where I can go to fix this? Can I access the SAM and edit it somehow? I know, that's stupid, but I'm getting testy here. Thanks!

It's more than likely an issue of group policies. Try forcing them. No break or I kill you!