From Andrew Connell ...

Configure a MOSS 2007 Publishing Site with Dual Authentication Providers and Anonymous Access

... describes how you can create and configure a MOSS 2007 Publishing Site that will satisfy the following requirements:

• Allow content owners/authors to authenticate on the site using their corporate Active Directory credentials in order to manage the Web site's content.
• Allow unauthenticated, anonymous users, to browse the unrestricted areas of the Web site.
• Require anonymous user to provide a friendly Web-based form to login in order to consume restricted content.
• While the article explains how to do it for a MOSS 2007 Publishing Site, this technique will work for any site based off WSS v3.

It walks you through the steps of:

• Setting up and configuring a data store to keep the Internet user's credentials
• Creating two Web applications, one for each authentication mechanism
• Configuring the Web applications to communicate with the data store
• Enabling Forms Authentication on one Web application
• Enabling anonymous access
• Configuring a section of the site for authenticated users only

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