Originally Posted by WhicheverAnyWayCan
I'm having the same problem. Wonder if your came with SD Card? The person who sold it to me didn't include his.
Garmin does not include uSD cards with the Montana, or any other GPS. Vendors may include special packages with uSD cards, but the only maps above and beyond the BASEMAP that garmin ships with the Montana are the 100k Topo map, and it is pre-installed on the GPSr, not on an uSD card.
I suggest some reading here
to help you in a productive direction.