AFP not recognizing the Serial port
 

I used to have AFP on my laptop and everything worked fine. I recently got rid of the laptop and purchased a desktop. I installed AFP and everything went smoothly, but when I try to run the program, AFP searches for the interface cable, which plugs into the computer's Serial port, but doesn't recognize that the interface cable is plugged in. Has anyone had this problem before and if so how did you fix it? I am not sure whether it is a problem with AFP or my computer, hopefully AFP since the computer is new. Thanks.

Josh