with a whitelist associated with the recipient and fails to identify the sender the mail sever then sends an email to the sender requesting that they supply some form of verification upon receipt of the verification at the mail server the sender is added to the recipient 39 s whitelist and the queued message is forwarded to the recipient 39 s mail spool when further emails are sent by the sender to the recipient the whitelist will be checked and the senders address identified consequently the sender 39 s email will be forwarded to the recipient 39 s mail spool where a spammer sends an email to the recipient the mail sever intercepts that email and checks whether the sender 39 s name is on the whitelist the server then sends a verifying message to the forged email address in this case the spammer will never respond because the address has been forged the email will therefore wait at the mail server for a pre determined period without being sent to the recipient before being deleted a similar result will occur if the sender 39 s address is not forged but simply consists of an unmanned u201c drop box u201d where a spammer develops a mechanism to reply to the verification message at a great cost to the spammer the invention can be implemented with a higher level of verification security a flowchart illustrating the steps according to one particular embodiment of the present invention is shown in fig1 the email is received at a mail server associated with the recipient the server then compares the address of the sender with a system wide blacklist that is a list of senders.