Georgia-
Had the same problem (with the serial cable) and discovered that the hotsynch for my Palm was blocking all the ports. I did a right-click on the hotsynch icon and unchecked the serial option and the GPS worked just fine.
Hopefully, that's the easiest fix.
Hey, great thread. I'm still green with my new GPS and wanted to try it out on some benchmarks in the area, so your "kitbags" are very good information.
One question - nobody brings a map?
-Tony