NT Challenge and Response window on virtual directory in IIS 7.0

I have set up a simple virtual directory that contains common C开发者_开发技巧SS style sheets and image files on a web site hosted under IIS 7.0 and I keep getting the NT challenge and response window when I try to browse to the web site.

How do I prevent this from happening?

Where does the virtual directory live and what are the NTFS permissions on it?

When IIS is installed the permissions on inetpub\wwwroot are set to allow IIS to access that directory, and any directories under it will inherit the permissions. I am guessing your virtual directory points outside of the normal web directories, and thus the NTFS permissions for the directory and the files within it exclude IIS.

To fix this open explorer and navigate to the directory above the directory your virtual directory points to. Right click it and view the properties and then select the security tab. You will need to Edit the permissions and, at a minimum, give the IIS_IUSRS group Read/Read and Execute/List folder contents rights. If your app pool is running as another user you'll also need to give that account the correct permissions.