@Bellmac

Welcome to GPS Power and congratulations on making your first post here. Please make your next post as an intro thread in [Only registered and activated users can see links. ].

Worst case is that it's suffered some kind of hardware failure and if so, no software solution will help. Best case is that it's accessed some corrupt data while in use and that's temporarily 'soft-bricked' it. Let's assume the latter until proven otherwise.

Seems some of your info is contradictory. You say it's not "properly getting into pre-boot mode by plugging in the USB cable". However, preboot mode is required both to use G7ToWin and flash an RGN file with Updater.exe and you've been able to do so. BTW, GarminExpress uses only Mass Storage Mode or Media Transfer Proticol, neither of which are available unless a device can fully boot. Preboot is invisible to it. WebUpdater on the other hand can use preboot mode (aka "Garmin Mode") as well as MSM/MTP. Lack of MSM/MTP is also why Windows doesn't recognise it ... however when you press the upper LH screen corner Device Manager will see it under "GARMIN Devices" in preboot but only for about 30 seconds unless a flash is initiated.

It's unclear what you used to make Cure firmware. If you used the MTK version (for HWID 1104) and named 11041000630.rgn, then Updater would refuse to flash it because the file name and actual device's HWID don't match (Updater queries the device to check). Using the QuickCure RGN would flash however, if named 097201000630.rgn even though it's actually universal and HWID independent. QC3 doesn't always work to reenable MSM in all device-types and series, but in my experience, it has worked with all soft-bricked nuvi 1xxx devices to restore MSM. Keep in mind that a device with correct Cure3 or QC3 fw loaded will still appear to be 'bricked' because it sticks on the logo screen as it's designed to do, but importantly with MSM reenabled. The sole purpose of any cure fw is to stall the boot process BEFORE any essential files can be loaded. No corrupt files are used in the partial-boot even though they're still onboard.

So here's the link below to HWID 0972 V6.30 firmware. Re-make Cure3 from it named only "097201000630.rgn" and try to flash it.
Code:
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If it does successfully restore MSM, follow the steps in "How to Unbrick ...." thread but keep in mind you might not need to re-format but only remove some files (see the initial post in the Cure3 thread). It you do have to re-format, use only RMprepUSB with correct settings and make a full file system backup beforehand too. If unsure, don't worry. There are no silly questions as far as i'm concerned so ask first - i won't bite ..... unless you don't make an Introduction thread in Members Presentation!
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