I have noticed that the auto update overwrites the 'My data' file on the c510 everytime i download new POI's. I have loaded the speed cameras and red lights and then tried adding resturants only to find that the data for the redlights and speed cameras being overwritten. Any thoughts?
windi3, I am not very advanced either but .. I am not sure what you refer to as "auto update" ? If you are referring to using "POI loader" then I can offer the following.. POI loader does delete existing files called "poi.gpi" on your GPS as it installs a new one - as you have observed. You need to keep a folder on your computer with all POI files in it. When you get new or updated POI files, add them to this folder on your computer. Use POI loader to install them ALL into your GPS as a single file called "poi.gpi" (deleting the existing one).
However, you need to investigate the naming of the file "poi.gpi" (containing all the POI data) - apparently it can be renamed but KEEP the extension - the part after the dot - it should be ".gpi". If I understand it correctly, the file on the GPS can be renamed and another poi.gpi file can then be installed. The GPS will apparently search all ".gpi" files during normal operation. I have just looked in my 3790T and I see ten files ending with .gpi and only one of them is poi.gpi. PLEASE let me know if you find this helpful.