I went to a website described on YouTube, and downloaded a Garmin North America map. This file is unlocked and I changed the name to gmapsupp.img and put it in a file entitled "Garmin" on a formatted 4GB SDHC card. According to this YouTube website, this should have worked, but I am having no luck. I know that the SD card works in the Nuvi 200 because a photo that I put on there displayed on the Nuvi. Also I updated the software on Garmin express so I know that that is not the problem. I hope that someone can tell me what I am doing wrong.