After publishing the initial default set-up of BlogEngine.NET ( http://www.dotnetblogengine.net/ ) to an IIS 7 web server (i.e. not running under debug mode from Visual Studio), the following security exception may appear, stating : System.Security.SecurityException: Request for the permission of type 'System.Web.AspNetHostingPermission, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed. BlogEngine.NET Security Exception To get BlogEngine.NET running, the "User Profile" of the application pool that the application runs under in IIS needs to be updated. IIS 7 Application Pools The "Load User Profile", accessed through advanced settings of the application pool, needs to be set to true. Application Pool Advanced Settings - Load User Profile That should be it to get a proper response from BlogEngine.NET on the server. Of course don't forget to add write permissions for the app_data folder. Thanks to David Burke ...