http://support.microsoft.com/default.aspx/kb/90727 3

HTTP 401.3: Denied by resource ACL
Description

This error is returned when the user successfully authenticated to the server, but the user does not have NTFS permissions to the content requested.

Common solutions
Set the NTFS permissions correctly on the content. Review the "NTFS Permissions" section in the following articles:
812614 (http://support.microsoft.com/kb/812614/ ) Default permissions and user rights for IIS 6.0
271071 (http://support.microsoft.com/kb/271071/ ) How to set required NTFS permissions and user rights for an IIS 5.0 Web server
187506 (http://support.microsoft.com/kb/187506/ ) Required NTFS permissions and user rights for IIS 4.0
Verify that the correct authentication method is set. For example, when you use Integrated authentication, users are not prompted for authentication credentials. In this instance, it may be unclear if the request is authenticating or not.
If the content is located on a remote share, verify that users have sufficient NTFS and Share permissions. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
332142 (http://support.microsoft.com/kb/332142/ ) NTLM requests for content on UNC share may be returned with 401 error messages