I have a 2TB WD external hard drive, which the power adapter is malfunction, so I bought another adapter to replace it.
The voltage (12V) and Ampere (1.5A) of the new power adapter are same with original, but I overlooked that the polarity
is reversed, and the harddisk is now like unformatted/unpartitioned drive, and not shown in My Computer.

I have taken out the harddisk from the casing and used USB harddisk docking station + Zero Assumption Recovery v9.2
and O&O DiskRecovery v7.1 and tried retrieving data, but no files nor folder was found after more than 10 hours processing.

Any idea that I should supposedly do in order to recover the data? Thanks in advance.

My Book Essentials models are encrypted. You need to repair the bridge PCB, or replace it.

Can you upload a detailed photo or CCD scan of the damaged USB-SATA bridge PCB? Sometimes there is an easy DIY fix.

_________________
A backup a day keeps DR away.

Some people claim to be able to decrypt an encrypted image obtained from such drives. There's one who is a member here, and another whom I found on the Github page for a tool called Reallymine (not the author, but you could also ask the tool's author for advice). I could send you that person's direct e-mail by private message. I contacted him while trying to help someone who had to decrypt an external Western Digital HDD after the password was lost, but that person (the drive's owner) renounced for now, so I couldn't confirm that it does work, although I've received detailed explanations as to what can be done (among other things, it depends on the type of chip used on the USB bridge).

If you can, do a complete drive image or clone with the drive connected through your docking station (hopefully it's a USB 3.0 model, because if it's USB 2.0 you're at least tripling the time needed to perform any of those operations, since the bandwidth is limited to about 35MB/s, while a HDD of that capacity can reach more than 100MB/s, some models are even closer to 200MB/s ; if you have a desktop computer, it's preferable to connect it directly in SATA to benefit from the highest speed possible). It will be encrypted, but at least you will have that as a backup if anything goes wrong.
Then attempt to find a PCB fix as “fzabkar” suggested : if it works it will be a cheap solution.
If it does not work, then you will still have that image/clone, and one of those people might be able to help you decrypt it (for a price obviously).

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