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If the class enrollment changes frequently, it can be cumbersome to manually update the group. Another method to prevent Guests from accessing specific material in the course is to override the permissions for those items. To do this, go into editing mode and click on the Update icon for the item you wish to limit access to. Then click Settings → Permissions. Select the "Guest" role Under Advanced role override, Select the Guest role and change the viewing permissions to Prevent. For example, when limited access to a file, you would change the View resource value to Prevent.