Sorry for any and all newbie stupidity. I have a nuvi 855. When trying to update the maps, I accidentally deleted the original gmapprom.img and gmapprom.sum. Is there a way to get these back, or will it matter if I use one of the install methods to "update" to a newer map version? Sorry, new here, haven't tried anything. Just hope I don't have a $175 paperweight now. Thanks for any help.