Get data from USB UART, but not USB-to-Serial adaptor

I have written a sketch for Arduino that sends serial data to my VB.Net app. Works great using the included USB port on the board. I need more distance, so I installed a MAX232. This is interesting. I get proper data in TeraTerm for both com ports (the Arduino USB comes up as a com port). I get proper data in my VB app from the Arduino USB (com) port. I get nothing from the MAX232 circuit on the other com port in my VB app. Why would both work in TeraTerm, but only the USB cable on the Arduino, not my MAX232 circuit in my application?

Handshaking?

Please be more specific.