Discovery fails when using UPN (User Principal Name) credentials

Overview

This article outlines information regarding discovery failures when using UPN credentials.  The following error may appear:  "Access is Denied. The windows credentials cannot be used to connnect to the windows server <machinename>."

Details

UPN Credentials will only work in a Windows 2000 domain environment and if your environment is configured to allow UPN credentials.  To configure your Web site to accept UPNs when you are using Basic authentication, perform the following steps:

1. Open the Internet Services Manager (or custom management console that contains the IIS snap-in).
2. Expand your Web sites, and then click to highlight the Web site where you want to enable the UPN logon.
3. Right-click the Web site, and then click Properties.
4. Click the Directory Security tab.
5. Under the Anonymous Access and Authentication Control section, click Edit.
6. Next to Basic Authentication, click Edit. (Note that this step assumes that you already are using Basic Authentication. If you are not using it, click to enable the Basic Authentication check box and make sure to disable other forms of authentication).
7. Under the Domain Name section, insert \.
8. Click OK, and then exit the Web site property sheet. (Make sure to click OK on the other windows to ensure that your changes take effect.)

For more details regarding this, please see the following Microsoft Knowledge Base Article:

http://support.microsoft.com/?id=260269