GetObject permissions on an authenticated page

I've got an ASP page that is protected by Integrated Windows Authentication. On this page is a script that uses GetObject to find the logged-in user name within specific security groups and set global variables accordingly.

I'm having problems with the script running properly, however, when the page is protected. I get an 80072020 error when the Windows Authentication is in place. This error disappears if I disable the authentication and enable anonymous access. Apparently what's happening is that it's running the script using the credentials of the logged in user who apparently doesn't have permission to view the members of the group.

When I put the code into a .vbs file and execute it from a command prompt on the server, it works fine. I thought maybe creating a WSC containing the code that is generating the permissions errors would circumvent the problem (after all, my understanding is that the server would be executing that code separately), but it's giving the same error 80072020.

So my question is whether it's possible to have IIS protect a page with Windows Authentication but specify that the script within the page be run by the anonymous IUSR account.

I'm sure this sort of problem isn't terribly uncommon, but I searched for hours without coming up with a clear answer.

Thanks so much for any help,
Mike