A diagnostic handling server is capable of supporting users without operator support, in which the proper handling of a problem, which users know through experience, can be reflected in the support. Preliminarily, data (e.g., dissatisfying item data) on the item with which a user feels dissatisfied and diagnostic data on the diagnoses of the electric appliances are collected from the electric appliances to be supported. The feature points of the respective electric appliances with which the user feels dissatisfied are then extracted from the collected diagnostic data. When the user feels dissatisfied with a specific electric appliance, the diagnostic data of the electric appliance is transmitted together with a search request for the proper handling, the transmitted diagnostic data is compared with the preliminarily extracted feature point, and information on the cause and the proper handling is provided to the user.