WebDav: Prompt for Credentials When Accessing FQDN Sites From a Windows Vista or Windows 7 Computer

http://support.microsoft.com/kb/943280

Click Start, type regedit in the Start Search box, and then press ENTER.

1. Locate and then click the following registry subkey:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WebClient\Parameters
2. On the Edit menu, point to New, and then click Multi-String Value.
3. Type AuthForwardServerList, and then press ENTER.
4. On the Edit menu, click Modify.
5. In the Value data box, type the URL of the server that hosts the Web share, and then click OK.
   
   Note You can also type a list of URLs in the Value data box. For more information, see the "Sample URL list" section in this article.
6. Exit Registry Editor.

After this registry entry is created, the WebClient service will read the entry value. If the client computer tries to access a URL that matches any of the expressions in the list, the user credential will be sent successfully to authenticate the user, even if no proxy is configured.

Note You have to restart the WebClient service after you modify the registry.

Sample URL list

The following is a sample URL list:

https://*.Contoso.com
http://*.dns.live.com
*.microsoft.com
https://172.169.4.6

This URL list enables the WebClient service to send credentials through the following channels.