In association with a spread of e-mails, the e-mails have been used for various applications. Not only used as means for office liaisons, the e-mails are used as means for advertising and publicity. The e-mails used as means for advertising and publicity include e-mail newsletters, spam mails, or similar mails. These mails are regularly or irregularly distributed to introduce articles, goods, or similar items specialized in a certain specific field.
Some users may think that the e-mail newsletters are unnecessary from this time on or browsing the e-mail newsletters is troublesome. Additionally, the spam mails are originally not preferable. Accordingly, means for stopping distributing the e-mail newsletters and the spam mails have been proposed.
For example, the invention disclosed in Patent Literature 1 proposes the method that receives the e-mail informing the junk mail from the recipient to stop distribution to this recipient.