@Caty, maybe it's a cr@ppy backup by GarminExpress which doesn't save the Garmin folder.
@Cal
Then just use G7ToWin in preboot mode. Open the program, press File>Configuration to set it up for USB as shown in the [Only registered and activated users can see links. ], press OK to get back to the small GUI, select 'GPS' and have the mouse cursor positioned over 'Get GPS ID' in the dropdown list:
[Only registered and activated users can see links. ]
Hold the top LH crn of the nuvi's screen while plugging in the USB and when you hear the ding dong connection tone quickly click on 'Get GPS ID'. If you get an error screen just click thru it. You'll see this screen then which is showing one of my 1390s as "ID: 972" meaning it's HWID is 0972:
[Only registered and activated users can see links. ]
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