This policy setting allows you to specify whether the app registration is completed before showing the Start screen to the user. By default when a new user signs in to a computer the Start screen is shown and apps are registered in the background. However some apps may not work until app registration is complete.If you enable this policy setting user sign-in is blocked for up to 6 minutes to complete the app registration. You can use this policy setting when customizing the Start screen on Remote Desktop Session Host servers. If you disable or do not configure this policy setting the Start screen is shown and apps are registered in the background.