Firstly you need to establish that your GPS is Compatible. In principle this means it runs the WindowsCE operating system and the user interface allows you to launch a 3rd party application.
Memory-Map branded maps do not work on a Garmin GPS (or Magellan, lowrance, etc.) These GPS units use proprietary formats and only accept mapping products specially made for the purpos
First make sure you have Memory-Map ver 5.4.2 or later installed on your PC. In your Memory-Map software see Web > Check for updates. For the transfer of Overlay data