Preloaded BlueChart g2 maps on a GPSMAP 478 are not displaying in HomePort

Even though HomePort is capable of reading and displaying the BlueChart g2 maps, the maps that are preloaded to the GPSMAP 478 cannot be viewed in HomePort.

By connecting the GPSMAP 478 to the computer using the USB cable, you can transfer user data (waypoints, routes, and tracks) between the device and HomePort, but HomePort will not be able to read any of the preloaded maps or any maps on a Garmin Data Card that may be inserted into the device.