Does anybody have NAT32 successfully running on a computer protected by ZoneAlarm (or any 10.0 version)? I'm having a terrible time getting the two to coexist!

My system: I have a second PC hung off my primary PC, connected by a CAT5e crossover cable (running from ethernet adapter to ethernet adapter). Internet access to the primary PC is provided via wireless. NAT32 is described as a "Windows Software Router." It runs on the primary PC and allows the second PC to access the Internet through the cable and the primary PC's Internet connection.

The technical specifics: On the primary PC, the ethernet adapter is assigned an IP address of NAT32 takes that and creates a Private LAN with a gateway of Clients then have to be assigned an IP address of 172.16.2.x (where x is a unique number other than 0, 1, 100 or 200). The ethernet adapter on my secondary PC is assigned, with the default gateway set to The configuation is correct, because it works under certain circumstances (keep reading).

I have ZoneAlarm running on both machines, but the problem exists entirely with the installation on the primary PC. If I disable that installation of ZoneAlarm, NAT32 works without conflict and I can access the Internet from the second PC with no difficulty. However, if I turn on ZoneAlarm on the primary PC, the second PC cannot access the Internet; something about ZoneAlarm is blocking it. I've tried every configuration I can think of to allow access, but nothing's worked.

For example, I went into Application Control and customized the settings for NAT32 ("NAT32 Enhanced IP Router for Windows"). I checked both "This program may use other programs to access the Internet" and "Allow Program Interaction." I changed the Trust Level from "Ask" to "Trusted." That didn't fix the problem.

I went to Firewall Settings and created a new Trusted zone for the secondary PC ( Again, no change. I deleted that and set up a Trusted zone for an IP range ( to that included everything controlled by NAT32. Once again, no change.

I even did all of the above at the same time. Still no change.

I'm just about at my wit's end. Any suggestions? I would have thought this would be a straightforward problem to resolve, but it's completely eluding me!