I'm running a web application which uses an AJAX script to post data to a form in a separate file but on the same domain. The application is configured to use Windows authentication. When the AJAX script is activated though I receive a network username/password prompt. If I provide my network credentials and click OK then the script runs fine and thereafter I'm not prompted for authentication again, but I don't see why it should happen in the first place. If I change the authentication to anonymous access on the specific file that is posted to it doesn't receive the post data for some reason (Request.Form.Count = 0). Any ideas?