Abstract: A mail processing apparatus includes a data retrieving section for retrieving sample data from e-mail and/or a network NW, a signalizing section for converting the sample data form the data retrieving section into n-value, a sample storage section for storing n-value data converted by the signalizing section, a signal processing section for comparing the n-value sample data stored in the sample storage section with an inputted e-mail to judge whether or not the e-mail is spam mail based on the degree of similarity, and a spam storing section for storing the spam mail based on the judgment result.

Abstract: An e-mail processing system includes an e-mail received from an external apparatus through a network and a managing center that manages the information regarding spam mails. An e-mail system detects a spam mail from the received e-mail based on the information received from the managing center, and user PCs that receive a legitimate e-mail other than spam mails, through the e-mail system.