@mmcabe: I am new also. I ran into the same type problems you are, using a Valley Enterprises cable, a Yaesu FT-60, and a Macbook. I solved it by reloading all 3 software apps again...Chirp, Python and PL2303...those being the software apps needed for my Macbook. Fearing a repeat need for this requirement, I have left my computer running since the software re-installs. But give this approach a try. It did work for me. And make SURE you execute the correct steps in the exact CORRECT ORDER vis-a-vis the computer/radio or you will get the same "errors" displayed that are bothering you now.. Good luck.