Abstract: The system filters-out undesirable email messages sent to a user email address. The system includes a data store providing updateable storage of signature records that correspond to a subset of undesirable email messages that may be sent to the predetermined email address. An email filter processor is coupled to the store of signature records and operates against the email messages received at the predetermined email address to identify and filter-out email messages corresponding to any of the signature records. An update system is provided to automatically receive a set of signature records, which are then used to update the plurality of signature records stored by the data store. The system can be implemented to include at least a portion of the email processor system within a client site email transport system, which receives the email messages addressed to the set of email addresses assigned or associated with the client site, including the predetermined email address.