In the case of a managed installation, the package author may need to limit which public properties are passed to the server side and can be changed by a user that is not a system administrator. Some restrictions are commonly necessary to maintain a secure environment when the installation requires the installer to use elevated privileges.
If this per-machine system policy is set to "1", then the installer can pass all public properties to the server side during a managed installation using elevated privileges. Setting this policy has the same effect as setting the EnableUserControl property. Setting this policy allows all public properties to be passed to the service and to be changeable by nonadministrative users. By default, this policy is not enabled; only restricted public properties are passed to the server side and changeable by a nonadministrative user. All other public properties are ignored.
If the operating system is Windows 2000, the user is not a system administrator, and the application or product is being installed with elevated privileges, then a user that is not a system administrator can only override an approved list of restricted public properties. For more information see Restricted Public Properties.