I'm using Keyspan Hight Speed USB Serial Adpter P/N USA19QW to run K2 for HamRadio Delux on ThinkPadX24(Win2K). USA19QW latest software is version 3.1. HamRadio Delux connect setting is as follow. Company: Elecraft Radio: K2 COM Port: Auto-detect Speed: 4800 I have no ploblem. Thanks, -gamy, JH3EGA