T 5.75 Overload due to incoming e-mails

An e-mail address can be blocked intentionally by being constantly sent large e-mail files (possibly with unintelligible contents). This can happen, for example, to users who have not observed Netiquette and thus made themselves unpopular in news groups. Netiquette (network etiquette) comprises rules of conduct which develop in the course of time among users of the Internet, particularly newsgroups. These rules are meant to allow efficient and satisfactory use of the Internet for everyone.

An intentionally high volume of traffic can overload the local mail system, thus rendering it inoperable. This problem can become serious enough to make the provider disconnect the user's organisation from the network.

A mail system can also be overloaded by employees engaged in the forwarding of chain-letters. During a Christmas season in the mid-Eighties, one such chain-letter campaign paralysed several IT systems worldwide. Users received an e-mail with Christmas greetings including a bitmap, and were requested to copy this mail and forward it to ten other users.