A license management server manages a license to perform a service of remote maintenance related to one or more image forming apparatuses installed in a customer's site. The maintenance server includes a maintenance unit and a history management unit. If the license management server notified of expiration of an expiration date of the license defined by a contract, the maintenance unit stores history information acquired from the one or more image forming apparatuses corresponding to the expired license into a storage unit, and stops the service. If the license management server notified of grant of the license by a re-contract, the history management unit obtains the history information about the one or more image forming apparatuses corresponding to the granted license from the storage unit, and passes the obtained history information to the maintenance unit. By using the passed history information, the maintenance unit resumes the service.