Makes a reservation record for the HTTP Server API configuration store on Windows XP SP2, Windows Server 2003, and later. For more information about the HTTP Server API, see [HTTP Server API](https://learn.microsoft.com/en-us/windows/win32/http/http-api-start-page). The access control entries for the access control list. Extensibility point in the WiX XML Schema. Schema extensions can register additional elements at this point in the schema. Specifies the behavior when trying to install a URL reservation and it already exists. Replaces the existing URL reservation (the default). Keeps the existing URL reservation. The installation fails. Unique ID of this URL reservation. If this attribute is not specified, an identifier will be generated automatically. Security descriptor to apply to the URL reservation. Can't be specified when using children UrlAce elements. The [UrlPrefix](https://learn.microsoft.com/en-us/windows/win32/http/urlprefix-strings) string that defines the portion of the URL namespace to which this reservation pertains. Extensibility point in the WiX XML Schema. Schema extensions can register additional attributes at this point in the schema.