Garmin POI Loader (v 2.4.0 or higher) has an option to uninstall all custom POI's from your GPS.
Using this feature doesn't remove the regular built-in POIs that were pre-installed on your GPS.
However, for units that come preloaded with the the NTTS trucking database, it appears that POI Loader DOES delete this information. Like custom POI's, it's stored in a GPI file.
Microsoft Excel can read .csv files, but so can many other programs. When Excel is installed on your computer, it automatically associates the .csv extension with Excel. This is why the files show with an Excel icon.
If you look closely at the icon, you'll notice it's slightly different than the icon that's normally used for Excel spreadsheets / workbooks.
Even though these models have a SD card slot, they cannot read custom POI data from a SD card.
Several users have reported confirmation of this from Garmin technical support reps. The attached discussion topics include some examples of email responses from Garmin.
Garmin's POI Loader software can read .gpx (GPS exchange format) and .csv (Garmin comma separated values) files.
POI Loader will also read Icon files (.bmp) and Sound files (.mp3 and .wav).
Note that if you use .wav files for sound, you must have sox.exe (see http://www.poi-factory.com/node/25730 for details) in the same directory that contains POI Loader.exe.
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