E-mail firewall

An e-mail firewall ( 105 ) applies policies to e-mail messages ( 204 ) between a first site and a plurality of second sites in accordance with a plurality of administrator selectable policies ( 216 ). The firewall comprises a simple mail transfer protocol (SMTP) relay ( 202 ) for causing the e-mail messages ( 204 ) to be transmitted between the first site and selected ones of the second sites. A plurality of policy managers ( 216 ) enforce-administrator selectable policies. The policies, such as encryption and decryption policies, comprise at least a first source/destination policy ( 218 ), at least a first content policy ( 202 ) and at least a first virus policy ( 224 ). The policies are characterized by a plurality of administrator selectable criteria ( 310 ), a plurality of administrator selectable exceptions ( 312 ) to the criteria and a plurality of administrator selectable actions ( 314, 316, 322 ) associated with the criteria and exceptions. The policy managers comprise an access manager ( 218 ) for restricting transmission of e-mail messages ( 204 ) between the first site and the second sites in accordance with the source/destination policy ( 218 ). The policy managers ( 216 ) further comprise a content manager ( 220 ) for restricting transmission of e-mail messages ( 204 ) between the first site and the second sites in accordance with the content policy ( 220 ), and a virus manager ( 224 ) for restriction transmission of e-mail messages ( 204 ) between the first site and the second sites in accordance with the virus policy ( 224 ).