Blocking spam relaying and junk mail

The electronic equivalent of junk paper mail is quite often referred to as ‘spam’, or more technically as ‘UCE’ (Unsolicited Commercial Email’) or ‘UBE’ (Unsolicited Bulk Email). Strictly speaking, these terms are not really interchangeable, but in practice they are treated as synonymous. Some mass mailings advertise genuine products, but most spam messages, sent to thousands of ... ................
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