When preparing a bootable Ubuntu Live USB key from Windows, I made a giant mistake and quick formated a 2TB HDD. I realized it during formating, so I cancelled the operation from the Windows explorer GUI. On this disk was running a 1GB Ubuntu guest in a VirtualBox. I immediately shutdown the PC through the WIndows explorer dedicated functionaliity, then I tried some testdisk on it, then I removed the SATA and power cables from it.
In testdisk 6.2 is told that both MFT and its backup are corrupt

So I'm beeing shipped another copy of the same 2TB HDD tomorrow, and am ready to follow with a third-party software: Zero Assumptions Recovery, GetDataBack For NTFS, as advised in the testdisk documentation.
However, I read that it's safer to clone the faulty HDD first, by using UNIX "dd" sectore cloning for example. I'm knowledged on doing this.
But I need to understand:
- Do recovery softwares write on the faulty disk? I've in mind that they only read it, dynamically build a MFT into RAM, and allow user to copy files to any other safe partitions
- I have a faulty 2TB to recover, and a supposed healthy and blank 2TB to receive the recovered files: If I use a recovery software on the faulty disk, without cloning it on the other disk with "dd", I'll have 2TB free space to receive the recovery
- On the other hand, if I clone the faulty disk on the other one, with "dd", I'll need a third HDD to receive the recovered files, and I don't have a third HDD
Thanks in advance for your inputs, I really have very important work data on this disk, and I'm learning to be cautious as of now
