Try kunix's cure, sticky thread
Good evening, just on the problem.
previously, my garmin nuvi 50lm damaged software. nuvi 50lm beginning I could not read a map, when lit then go to boot "loading map", restart my Nuvi. and so on. then i update using software updater to replace a 52lm to 50lm, HWID 1350. but the problem then arises, gps can be used, and can fit into the system garmin, but can not read a map, there is a description of "no detailed maps that support the routing.the nuvi can not be used without them". I think to do a hard reset, but after doing clearnonvol, gps then stopped and could not do clearnonvol. what should I do?