I have created a mapset using Mapsource, and saved it to my computer as a .gdb file. The mapset file is 240MB but the .gdb file is 4kB. Can someone answer the following questions please ?

1. Is the .gdb file a control file for loading data into Mapsource/Basecamp ?

2. If so , why can´t I load the .gdb file into Basecamp when it works ok with Mapsource ?

3. If I send the mapset to my GPS,what will be the filename that is created ?

Thanx in advance.

*.gdb (Garmin DataBase) is the "native" file format of MapSource for Waypoints, Routes, Tracks and Mapsets.
BaseCamp can im- or export this file format, but only the Informations about Waypoints, Routes and Tracks, because Basecamp don't work with mapsets.

The file format for Garmin maps used on Garmin devices and created by MapSource/MapInstall by sending to unit or SD is *.img. But it is not compatible with other *.img formats (e.g. CD/DVD image).

Thanx p!xeldealer.

So if I save .img file to gps or sd card , I can select this from map options in gps ? Doesn´t have to be called gmapsupp , gmapprom etc ?

Sorry to be a pest !

On your device (nuvi 255w) and all other units of this and older generations you must use the gmap****.img names, as described >>>here. Only newer devices can use any name with extension .img.