An administrative server interconnects user terminals through the communication network and transmits voice and/or text information submitted and received between the user terminals to a storage device. The server records in the storage device the voice and/or text information together with identification information of the user terminals that have submitted said voice and/or text information. The server retrieves words that disobey morals in the voice and/or text information recorded in the storage device. The server records disobedient data which indicates disobedience in morals in registration data of the user who submitted the voice and/or text information retrieved by the retrieval and presents the disobedient voice and/or text information and the identification information of the user at the submitting side to an administrator control table of the administrative server.