I am developing a master page which includes the user control that generates a menu from the list with a specific logic. Before including the control into master page I successfully configured anonymous access to the site. After including the control and deploying - site prompts for user name and password. I allowed the anonymous access to the list. Oh yes ... It worked on SHarepoint 2010 beta, but the problem happens when deploying to the Sharepoint 2010 final release. Additional data: I am using Sharepoint Server 2010 with Standard features, standalone instalation on Windows Server 2008 R2 for deployment, and Visual Studio 2010 Ultimate for development of masterpage and user control.