Use program G7ToWin to retrieve your HWID
First, configure it correctly for USB (some very old units use a COM Port not USB):Code:Please Login or Register to see the links
(thanks Alexander for the screen )
Connect device in *[Only registered and activated users can see links. ] after selecting COM Port/ USB and in GPS menu click on Get GPS ID-
*Older 'region-only' devices without a visible file system are in a perpetual pseudo-preboot so may simply be connected while following any prompts on the device screen.
Or for units with a visible file system look at Garmin folder for GarminDevice.xml in Mass Storage Mode [See "<PartNumber>006-Bxxx-00</PartNumber>" where xxxx is 4 numeral HWID]. If you have a backup, look there.