DNN & Evoq sites run off a single Default.aspx page. Live Shield cannot just quarantine Default.aspx by renaming and adding “.resources” if it is replaced or modified since that will cause the site to throw error.  

Live Shield automatically creates an app_offline.htm to gracefully bring the site down and shows a maintenance message with Live Shield Message ID: DC58B if any tampering is detected with Default.aspx. An administrator can customize the app_offline.htm.shield in root directory to change the maintenance message and branding of app_offline.htm