Hi, I am publishing my exchange server through ISA. This has worked fine for SMTP mail. The problem I am having, is that I have another internal SMTP server. This server delivers mail properly to all external adresses but not the ones on my exchange server. When I telnet to any external SMTP server from this server it works fine, but when I telnet to my exchange server using the IP of the external NIC on my ISA server it does not work. Does anyone have a work around? Cheers, J.