Help: Lacie ext USB NTFS filesystem suddenly damaged. Boot sector repaired using Testdisk but got worse..

[Tatigo]

My Lacie ext USB 4T drive has two main partitions under GTP:
NTFS filesystem (F:)and a Macos HFS for Timemachine

Yesterday the NTFS partition suddenly damaged while watching a video file from F: disk then halt. Disk shows "RAW format" all the time after that halt.

Googled and resort to testdisk....
I tried quick intel scan and it says the "Boot sector" is bad.
Check the manual 7.4 tells that can try repaired using Testdisk 7.4 Repairing FAT32,exFAT and NTFS boot sector using TestDisk

Original good GPT partition is like ""EFI(200mb)---NTFS(3.6TB)---MAC.HFS(300G)""
before repair GPT partition is like ""EFI(200mb)---RAW(3.6TB)---MAC.HFS(300G)""



but after Repairing NTFS boot sector with a valid backup from I don't know where (but seems not identical) recover, my drive has gotten worse..
use Aomei partition check(which opens much longer time than usual)

After repair GPT partition is like "" Unformatted (2.0TB)---Unallocated Space(1.6TB)"" WTF???!!!

Shit!! Have I got fooled?? Is that a desperate situation for my data/ disk?
Please some kind people do advice what to do !!! Thank you!

[cgrenier]

Your disk is using a GPT partition table, so a "quick Intel scan" was useless.
Modifying the NTFS boot sector has no effect on the partition table (GPT or Intel).
Can you copy and paste the testdisk.log file content ?
I don't understand what mistakes you have made.

[Tatigo]

Thank you! cgrenier
Are you the creator of TestDisk? My respect.


The log shows nothing...like below, I didn't know what have been done by testdisk...

Tue Oct 15 12:05:53 2019
Command line: TestDisk
TestDisk 7.2-WIP, Data Recovery Utility, July 2019
Christophe GRENIER <grenier@cgsecurity.org>
https://www.cgsecurity.org
OS: Windows 7 (7601) SP1
Compiler: GCC 6.4, Cygwin32 2009.0
ext2fs lib: 1.43.1, ntfs lib: 10:0:0, reiserfs lib: none, ewf lib: 20140608, curses lib: ncurses 6.0


As you said Modifying the NTFS boot sector has no effect on the partition table (GPT or Intel). But my result after check that "repare attempted" disk, seems to me the partition recovery tool used previous disk partition backup (Lacie or GTP build-in) to overwrite my middle partition(the 3.6TB NTFS), which cause partition chaos after reboot..
I just hope theres a way to revert the rewrite of boot sector then use 3rd party tool (RecoveryRobot Parition Recovery / MiniTool Partition Wizard 11 )to salvage my DVD iso and photos.