VPN Local Intranet through separate adapter
I've got a PC with dual network adapters. The "host" PC is Windows 7 64bit. One of which is an network (net1 from now on) detached from the internet (192.168.1.xxx), and the other is a network (net2 from now on) attached to the internet (172.16.80.xxx). I need to be able to VPN into the net1 network remotely. Obviously I would have to come through the net2 network. What are my options, preferably free since this is the only device that I will be doing this on? I need direct access to all devices on net1.
I've tried Teamviewer VPN but it doesn't seem to do the trick, unless I'm missing something in the configuration.