An internet service provider (ISP) is configured to analyze a subscriber's sent e-mail packets to determine a subscriber identity associated with the e-mail packets. A database is then queried to determine a current sending rate of e-mails by the subscriber. A sending rate above an allowed threshold causes the upstream transmission of the e-mail packets to be blocked by injecting connection destroying packets. A subscriber remains blocked from upstream transmission of e-mails until the sending rate as determined by the ISP drops below a second, more stringent threshold. This automatic process is also accompanied by automated messaging to the subscriber with information as to the measures taken and remedial options.