sending outgoing text

I am a court reporter who connects her computer via custom software to
attorneys computers so they can see "live" feed of proceedings (think closed
captioning). This is sent via cables provided by our software company. I've
done this for years but since buying a new computer with Vista, my data
transfer times out and stops sometimes after 1 hr sometimes it's longer. I've
had someone do something ? to IP6 and User Account thinking that may be
the problem. No one seems to know. I'm desperate for an answer. Is it
possible
it could be the USB-serial adapator or is there some other security issue in
Vista I can "turn off." This has caused the loss of much $$$$$. Never a
problem with XP.
--
Sandi