SMTP Relay through ISA

[rubbaninja]

I have read through Shindlers Mail Relay chapter and still am having NO luck with SMTP relay. As a matter of fact, I cannot see the port open outside my PIX.

since it's probably a good idea not to explain my current configuration I will just tell you the network configuration.

Internal NIC 172.24.5.6
External NIC 172.24.6.6

Both nics on 3550 Switch which is on of 4 DMZ's
Internal NIC on VLAN 5
External NIC on VLAN 6

Internal NIC has an acl on PIX to allow inbound SMTP traffic to our Exchange server.
External NIC static translated to a pub IP with an ACL to allow SMTP inbound from ANY.

I installed IIS on this server and set up SMTP.
I fixed the socket pooling

So, any ideas on how to get this running?
I'm willing to start from scratch so if you have a way to do this based on the information of the network cards, please help.

Sorry about being vague but I don't want to give info on a possible misconfiguration.

Thanks!

 

[rubbaninja]

I figured out the problem.

Microsoft spoofing issue with one-to-one nat!

http://cert.uni-stuttgart.de/archive/ntbugtraq/2002/11/msg00004.html

Go figure.

I added the reghack and whalla!