Thread: Nüvi 3790

Yes it's as Boki said, the FOUND folder is not to do with the device itself - other that the actual file corruption source was caused initially by the device malfunctioning. I think at some point you've run CHKDSK, probably when prompted by Windows on connection of the device to PC. It's quite safe to delete that folder and the hidden "suspension/trash" folder with the video files as you've done to gain space.

I would hesitate to again re-format the file system however unless there are more corrupt files and folders later that refuse to be deleted. That may be ongoing in fact. Keep in mind that presently it's the nonrepairable corruption in region 41 that is at the root of all this device's problems. That has been shown to be uncorrectable by software means, neither clearing of delete-able data nor erase of the entire region works.

Only region 48 (the visible file system) is accessible by Windows built-in tools or by any other 3rd party software like MiniTool or EaseUS partition managers. The closest you can get to a conventional re-formatting of any region other than 48 is to erase it via an SD text command - do that to the wrong region and it might never boot again. For example, running "ergn,5" in Update.txt, if successful, would erase the bootloader which is roughly the equivalent of a PC's BIOS/UEFI firmware.

Note that if you do have to reformat the file system by absolute necessity, don't use anything other than [Only registered and activated users can see links. ] on a PC. A Mac will mess it up almost certainly and Windows (whether via Disk Management or any other 3rd party software) can be quite hit and miss. There are as many ways to format in FAT as skin a cat .... ... some work, some don't but for Garmin devices RMPrepUSB is totally reliable using the recommended settings.

EDIT: P.S. Sorry, forgot to say this: Re-flashing the firmware won't change anything in the File System, it'll only flash the firmware regions [aka the system software regions, 14 (0x0E) and 127 (0x7F)] and the ramloader in virtual region 12 (0x0C). Those regions are NOT your problem of course anyway. And yes Disk Management will detect an empty formatted drive. Windows File Explorer won't if Folder Options are set to not show empty drives:

Spoiler: click for image

[Only registered and activated users can see links. ]