Maybe you'd like to load the 37xx firmware treated with [Only registered and activated users can see links. ]. It's intended to enable all possible features in 3750/3760 so it might do something to your (now) 3700. I've had no experience with it used in an actual 3700 which i think was a regional European-only device, so I don't know what it will do to your device and it's all your risk if you try it. I haven't read that thread for years but i do recall there was conflicting info whether it worked in fw later than V4.90. If you want to try it, the original V4.90 is available here to patch:
Otherwise, you can go straight to erasing region 41 and cross your fingers that works, details about flashing text commands from SD using boot.bin as Ldr.bin are here: [Only registered and activated users can see links. ]. This is the command to use in Garmin\Updater\1101\update.txt:
'Thanking Posts' are banned. To thank someone, and/or to see hidden links and content, use the [Only registered and activated users can see links. ] button below left of the helpful post then refresh your browser [F5 key]. 'Thanking Posts' are banned. Please don't spam. Posts serving no purpose other than to thank or to ask about hidden links are trashed or deleted, it's GPSPower's policy. Please don't spam. [Only registered and activated users can see links. ] should make their first post as a new Intro Thread in [Only registered and activated users can see links. ].
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