Hello!
I use the same sequence as it was in the SG 2.80 firmware:
fw1_resources.bin
and last fw_all.bin
Copy all files from your Nuvi (so you could return them).
Change Text and Voice folders to 1Text and 1Voice (for example) in your Nuvi befor start to flash.
Delete the gupdate.qcd in the System folder if it is there.
Then start to flash alternative firmware through updater as usually.
In some cases it could be in the Garmin folder on SD card and for me it works.
But for alca777 the problem is to flash quickly when he press the top left corner.
I did it so:
Drug the original xxxxxxx.rgn file to the updater.
Press the top left corner and hold it.
Press Nuvi power button. Logo GARMIN starts.
Quickly connect the USB cable to your Nuvi.
Hold your finger on the top left corner and on the updater menu check the USB Device - ..Nuvi 1xxx.. -> And press OK.
Flashing starts (I hold my finger on the top left corner) .
When you see on the Nuvi screen - Loading...
You could remove your finger.
After the updater finish, close it
Remove the USB cable.
Turn off and turn on your Nuvi and wait for good load (a hope).
Luck
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