I have used proterm 2.1 to talk between a apple2gs and a win 2000 comp. You obviously have the cables set up right.. but my machine did not work properly unless hyperterm was set up to use software handshaking. FINALLY figured out what the problem was. I had the Super Serial Card settings set to exactly what the ADT documentation listed. The documentation for when I was creating a Apple // disk image for ADT from the PC. One of the dip switches needed to be turned on which would allow interrupts. Works perfectly now with hardware handshaking. = )