I think Windows defaults to exclusive opens on the com ports, so if program A has COM4 open, program B can't open it at the same time.
Try it from a fresh reboot before any othe rprogram has had a chance to commandeer the ports.
Lo and behold it works. I was trying the reboot like you mentioned - good idea but it didn't work.
What I think was happenning is I was leaving my GPS cable plugged into the converter when I plugged the converter into the laptop. All I know is that it works now! Yeah!
Thank you for all the help.