I copied the map file gmapsupp.img to a microSD card under /Garmin directory, then inserted into the GPS.

My GPS gives error messages: Cannot unlock maps, then a second error message says "the maps are either corrupted or ..."

I checked from PC side when connected with my GPS, BaseCamp is able to load the map, when I checked the map status, it was indicated as "unlockable", so I believe it's not an issue of locked map.

Any idea? Any way to make it work?

Thanks in advance.