Use Credentials

Key Use Credentials in ExCfgLvFdYF refers to a boolean that determines whether credentials are required for authorized web service requests to Yahoo and therefore should be used.
Set to TRUE to use such credentials each time a request is sent.
Set to FALSE to sent requests without using any credentials.
The default setting is FALSE because as of 17 Dec 2022 Yahoo stopped applying credentials on web service requests.
You will need to changed it to TRUE if unexpected errors occur that mught be due to a change in Yahoo's policy regarding credentials.