Quote Originally Posted by catymag View Post
To downgrade firmware easy method:
Plug nuvi USB, look for garmindevice.xml, change <SoftwareVersion>430</SoftwareVersion> to<SoftwareVersion>280</SoftwareVersion>. Save
Don't unplug nuvi from pc.
Having Garmin Webupdater on pc desktop, drag&drop in it [Only registered and activated users can see links. ] flash firmware.
My GPS has firmware 2.30 . The threads that I have read so far instruct to downgrade from 4.30 to 2.80 or 2.70 . So in my case, my GPS doesn't need a downgrade. So what do I need to do to get my nuvi 57 to read unlocked maps from an SD card? Thanks.