Quote Originally Posted by catymag View Post
the img has a PID over 2200 , with newer fw it cant work with *.unl, so use the locked img,dont use unlocked version unlock it with Fast Img Unlocker rename gmapsupp.img in a Garmin directory in sd, no *.unl, it must work.
Check also isnt named gmapsupp.img.img, enable estensions in windows to check.
This is almost literally what I did. See post #63:

Quote Originally Posted by smokefree View Post
I downloaded version 2010.30 from the link in post #27, renamed the file gmapsupp.img, unlocked it with Fast IMG Unlocker 1.5 and placed the resulting file in a folder named Garmin on an SD card.
I did download the locked version and unlocked it with Fast IMG Unlocker. The fact everything works fine when inserting the SD card into the nüvi 250W, tells me the folder and file on the SD card as well as the SD card itself are fine. Yet, no joy on the nüvi 350...