HTTP 401.1 Error (Invalid Credentials) with FrontPage Server Extensions 2002 - which suck, by the way.

Hello, fellow Experts.

I hate to admit it, but I'm totally stumped.  And over something as "simple" as FrontPage Server Extensions.

Here's the basic info on the server:

~ OS - Windows 2003 Standard w/ SP1; fully patched
~ Brand new install of IIS 6.0 and then ran Windows Update

Here's the basic info on the site in question (although I'm having the problem with all sites):

~ Created a site from scratch and pointed its root to a folder on the hard drive.  Let's pretend the path is F:\wwwsites\SiteRoot
~ The root of drive C: has the following NTFS permissions (not default permissions; Everyone group has been removed):
     - Administrators, CREATOR OWNER, SYSTEM = Full Control
     - Users = Read & Execute
~ The root of the site drive (F:) has the following NTFS permissions (not default permissions; Everyone group has been removed):
     - Administrators, CREATOR OWNER, SYSTEM = Full Control
     - Users = Read & Execute
~ The site root (F:\wwwsites\SiteRoot) has the following NTFS permissions:
     - Administrators, SYSTEM = Full Control
     - SiteUser (the user account for the end-user/site author) = Modify
     - NETWORK, IUSR_Machine, NETWORK SERVICE, OWS_xxxx_admin = List Folder Contents

I've installed FrontPage Server Extensions 2002 with IIS.  I right-click on the website, go to All Tasks and select "Install Server Extensions" and everything is happy and all of the little bits and bytes hug each other and dance a jig.  (By the way, I've installed this and assigned the end-user account as the site administrator and I've installed this and assigned the domain Administrator account as the site administrator... it seems to make no difference).

Once I've installed this, I right-click on the website, go to All Tasks and select either "Check Server Extensions 2002" or "Recalculate Server Extensions 2002 Web".  At this point, I am prompted for a logon.  I can logon as the local administrator, the domain Administrator or the site administrator (assuming it's not one of the other two) and I get the same web page (after three logon attempts):

*******************************************
You are not authorized to view this page

You do not have permission to view this page using your current user account.
Please try the following:


If you have another user account with a higher level of permission, click
your browser's Back button to try again using that account.
If you believe you should be able to view this page, contact the Web site administrator.
*******************************************

Well, I believe I should be able to view this page.  Unfortunately, I'm the Web site administrator and so far I haven't been all that cooperative in giving myself a solution to the problem.

If I right-click on the website, go to All Tasks and select "Remove Server Extensions 2002" and then click "Cancel", that takes me to the Virtual Server Administration page for this website.  If I click on the link to "Go to Site administration" at the top of the page, I get this lovely page:

*******************************************

You are not authorized to view this page
You do not have permission to view this directory or page using the credentials that you supplied.
--------------------------------------------------------------------------------

Please try the following:

Contact the Web site administrator if you believe you should be able to view this directory or page.
Click the Refresh button to try again with different credentials.

HTTP Error 401.1 - Unauthorized: Access is denied due to invalid credentials.
Internet Information Services (IIS)

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Technical Information (for support personnel)

Go to Microsoft Product Support Services and perform a title search for the words HTTP and 401.
Open IIS Help, which is accessible in IIS Manager (inetmgr), and search for topics titled Authentication, Access Control, and About Custom Error Messages.
 
*******************************************

I found a Microsoft KB article (896961) which specifies this exact problem and shows the remedy to be a registry hack to disable the loopback check introduced in Win2K3 SP1.  I've already applied this "fix" and rebooted.  No luck.

I've checked my authentication on the website and it is set to allow anonymous and Windows Integrated.

I've checked the Web Service Extensions and FrontPage Server Extensions are set to "Allow".

I had php, PERL and AwStats installed and I've removed all of them.  I then removed FP extensions and IIS and reinstalled them.  That didn't help either.

I've also cursed and threatened the server; apparently it's not intimidated.

If anyone can point me in the right direction, I'd certainly appreciate it.

Thanks!

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