title: IIS: Feature has been locked or read only when changing authentication
body: <p>We are currently migrating .net websites from 2008 to 2012. Most of these websites use anonymous authentication on the root, and forms authentication on an admin folder.</p>
  
  <p>I noticed that I'm unable to change these permissions in IIS. I keep receiving that the feature has been locked or is read only. I have checked my web.config to ensure there is no  section that would block this. Converting that subfolder to a separate website is not an option.</p>