Windows – Authentication Prompt is Looping Forever on Website Hosted on Internal Server in IIS

Well, typically when you have an IIS server on a DC there are all sorts of stuff that goes wrong:

• FrontPage
• WSUS

What I would look at is that the IUSR account is infact the correct one, and not the domain one - you actually might not have an IUSR account since it would have been domain specific.

This link has some information regarding IIS on DC's, and this link talks about promoting a member server to a DC. Here are details on the IUSR and IWAM accounts, which will probably have to be recreated and re-linked in the metabase.

"Added an IIS User" -> Do you mean IIS Manager user?

If so, these aren't real Windows users - just a username and a password in a text file somewhere: they don't have a SID or security tokens, and can't be used for Basic authentication. Not using the out-of-the-box configuration, anyway.

Create a (real) Windows user, and it'll be usable for Basic auth.

--

Edit: I just noticed you said something else - Feature Delegation doesn't describe permissions to the site contents, it's whether a non-Administrator can configure those features at a lower level within the site in a web.config file - essentially, which IIS feature icons are usable when they connect to the computer via the Management Service.

The answer is roughly the same, though:

• reset delegation to defaults (you didn't mean to change it; it's dangerous to change some of the delegation settings from defaults under these conditions)
• create a Windows user in Server Manager
• assign permissions to that Windows user either at the file system level, or using the URL Authorization feature