You cannot perform authentication of Web proxy requests through ISA Server 2004, Enterprise Edition by using a client certificate. The client Web browser establishes an end-to-end SSL connection with the external Web server computer through ISA Server 2004. In this scenario, ISA Server 2004 does not examine the packets in the encrypted tunnel.
For more information about common, unsupported configurations and scenarios that you may experience when you deploy and maintain ISA Server 2004, visit the following Microsoft Web site:
For more information about how to configure outgoing SSL requests in ISA Server 2004, visit the following Microsoft Web site: