I have only one Network card .. The server is connected to a small business Netgear router...So I assume you've configured your router to use your Server as DMZ Host, right? This would ususally be a scenario for dedicated LAN interfaces to separate DMZ traffic from local traffic. Though it might be possible to configure your firewall to get this separated somehow, I'd recommend to change your router configuration from using a DMZ-host to a NAT-Mapping. Your server will treat these requests like other internal requests and your router will do the mapping. Another positive side effect would be that your server isn't facing the internet directly and your "poor" windows firewall isn't supposed to handle all kinds of attacks including resource consuming port scans, etc.. That's what NAT routers are designed for.