Windows Small Business Server 2003 SP2
Setup as mail server with static IP address, 2 NICs, NAT and firewall
My new mail server is being blacklisted.
Spamhaus says it's because I have a client PC infected with a spam bot. I can see from the NAT Session Mapping Table which client PC is the problem, but they say I "must configure the NAT to prevent outbound port 25 connections to the Internet except from your real mail servers"
I need help doing that.
From "Routing and Remote Access", I can open my SERVER, go to "IP Routing" and see "NAT/Basic Firewall"
This lists my interfaces.
Right-clicking on my external interface and choosing "Show Mappings", I can see that one of my client PC's Private Address 192.168.1.14 is using TCP Outbound Remote Port 25 excessively. I want to block this for all clients (and then I'll fix the issue on the client PC!)
When I go to the "Properties" of my external interface, it is set up as a "Public Interface connected to the Internet". Both "Enable NAT" and "Enable a basic firewall" are checked.
I assume I need to setup an "Outbound Filter", but when I do and try to add a new filter, I have to enter a source IP and Subnet Mask, a destination IP and Subnet Mask and a protocol. The protocol would be port 25. When I try to enter 192.168.1.14 and 255.255.255.0 for the source, I get a message "The IP address and the subnet mask entered are not compatible. Confirm that both values are correct before continuing."
help.
Thanks,
Dan
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