If you setup a intranet or internal site, and setup the security as Integrated Windows Authentication – and you still have Anonymous Access on as well, but are still getting a prompt, it is most likely you are using a domain name for your site (like intranet.myinternaldomain.com) – The way to avoid getting a windows login prompt when hitting the site is to add the site to your trusted sites in your local zone in your IE tools->options, security tab.
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