Software which prevents the receipt of unsolicited email. There are two categories of anti-spam software. The first category prevents spam emails from being read by the user of an email reader. This type of software examines the header of an email; the part of the email that lists the sender; and the text of the message. It then rejects any emails which the user has notified as potential spam by comparing the contents of the email with a list of keywords, phrases, and known spammers' addresses. These are set up by the user prior to using the software. This type of software can operate either by scanning a mail server prior to emails being downloaded to the reader or by scanning mail which has been received by the reader. When spam is identified by a tool at the reader the tool places it in a special folder which can be perused by the user or just ignored and periodically deleted. Anti-spam software which examines mail in a mail server should be used with care since such software has been known to delete mail which is genuine. Programs in the second category of anti-spam software are used to process a spam email in order to determine where it has been sent from so that the recipient can mail a protest to the sender or the Internet service provider that hosts the user. There are a few anti-spam software programs on the market which combine both the functions of filtering email and determining the address of the sender.