1. A method of authenticating an electronic mail item, comprising: parsing a header of the electronic mail item to obtain an IP address of a sender of the electronic mail item from a transmission data mail header of the header and to obtain a purported sender domain name from a visible mail header of the header; interrogating a business entity database with the purported sender domain name to obtain an associated IP address of the sender associated with the purported sender domain name; comparing the IP address and the associated IP address of the sender to determine whether the IP address and the associated IP address match or not; generating an authenticity indicator in response to the comparison to indicate of likelihood that the electronic mail item is spoofed; and presenting the authenticity indicator to a recipient of the electronic mail item.