Many thanks for GarminCure3 tool so I can communicate with my nuvi 255 again. I updated the cure and my XP pc recognized my nuvi but I couldn't access the files in the directory without my computer hanging. I was also unable to copy the contents of the nuvi for some reason in order to create backup files. So in frustration I just decided to format using RMPREPUSB at these settings: Max/GARMIN/Set part as non bootable/MS DOS Bootable/Boot as FDD/Fat 32 and hope for the best. Unfortunately my nuvi now does not respond when I attempt to turn it on or off or attempt to pre-boot. It is stuck on unless I let it die or take it apart and disconnect the battery. So I am unable to get GarminCure3 to communicate in order to reload the original firmware. I've been reading about loading the firmware using an SD card but I'm not sure how to proceed.
Any assistance to get my nuvi 255 up and running again would be greatly appreciated.