Networking fails when not connected to the internet

We use a product that transmits information over TCP-IP. However, if the computer is not on the internet, we get the limited connectivity warning, and the info does not come through. Even if we set up on a static IP (No DHCP) we cant pass info. Often times, we need to have 2 programs running on the same machine exchanging data via the loopback adapter. But, as soon as the network cable is unplugged, it stops. Almost as if microsoft says No network connection, deactivate the network completely. Often, we are offsite and dont have access to internet and need the stack to stay active. Any ideas would be appreciated.