Thanks Neil for the information about Garmin StreetPilot 2720.
Found that post #3 from “ultrasheer” in this thread explains it all.
Creating .img-files with Mapsource and then proceeding with the WebUpdater-script in #3 shows that a file size of 1 815 168 kB fails while 1 796 064 kB works fine. After that both Mapsource and MapUpload(freware from wwwDOTmapwelDOTnet) reports Total Memory = 1 799 256 kB and 13-13.5 MB free space. MegaByte! Not much”
Testing with a new small, 10.5 MB, .img.file with script as in #3 will erase everything in SP2720 and now Mapsource can move the large area into the 2720.
Seems to me that WebUpdater.exe can unconditionally overwrite maps already in the 2720 while Mapsource/MapUpload can not.
/Gustav