You only need the .netcf if you have an older device. If you get that message it means you're trying to install to the storage card so the app can't find the OS. Try doing a reinstall - you'll need to download the installer fresh each time you do an install; you can't re-run it. Here's how.
Click Start, Settings, System and then Remove Programs and delete the FitSync installer. Then, via ActiveSync or Wi-Fi (not the carrier network because they could be blocking/corrupting OTA installs) go to
http://fitsync.com and download the installer to your device. Run the installer and install to device, not storage card.
Depending on your device, the installer may run through all the way by itself or you might have to tap OK after each step is completed (3 steps). You can also email us at
info@fitsync.com if you still have trouble.
John