I've used ADT 1.21 successfully between my //c and an old 8088 DOS laptop, but I can't make it work on my new Pentium PC. I keep getting "Unable to open com port" messages. (COM2 is the port, COM1 my internal modem.) But I can use Hyperterminal and do simple serial I/O with the //c, so I know the COM port works. Has anyone had this experience and/or a solution?