On a Microsoft Office SharePoint Server 2007 site, you enable "anonymous access" authentication.
You use Explorer View to view the document libraries.
In this scenario, you are unexpectedly prompted for authentication. Then, Explorer View fails if you do not provide credentials.
This issue occurs because the PROPFIND and OPTIONS methods are hard-coded to require authentication in the Httpget.cpp file.
To work around this issue, you can create two separate Web applications that host the same information. Where one Web application uses integrated authentication for internal use and the other Web application uses"anonymous access" authentication for external use. Additionally, you can also use forms-based authentication for Internet access.
You can then differentiate on which URL a user can see all content without being prompted to provide credentials by using the Web application that you set to use integrated authentication. Or, you can use the Web application that you set to use "anonymous access" authentication if you want to maintain the original behavior.