suggest de--install all mapsource maps & mapsource from the "control panel"--then delete the c:/garmin directory--
then with "mapset tool kit" remove all maps corrupted in the registry--

install mapsource and a map----it should work fine--
--------------------------------
when a mapsource map is made it works on the version that its creater used to make it--sometimes only that version--
installing a mapsource map is a crap shoot---

on the other hand a image file gmapsupp.img always works. without the hassle of mapsource--
------------
years ago large maps had way over the limit of 2024 map segments-and one had to use mapsource to export a map that was under 2024 segments,, and mapsource was the only way to unlock a mapset. and merging was only with mapsource--
older gps don't have enought memory to support large maps.
=
today we have maps with its unlock codes removed (correctly) we can merge with gmaptool-we can remove the lock codes with gmaptool. and we can use keygen to add a 25 digit code to the gmapsupp.unl file.

today mapsource is great for planning a hike with a topo map--