WD Tools ERROR at 95% full scan

Hi all!

I have a 4TB My Book external WD drive, and recenntly experienced the worst tragedy a BKP hard drive can experience: loss of power source during a transfer, that left me with 1 Tb of useless .CHK files on a FOUND.000 folder!

I obviously considered these 3,7Tb BKP completely lost, and proceeded to formatting the drive again and running all the test tools I have at hand.

I run Windows Check Disk twice and it didnt find any problem, after over 24 hours of scanning the drive.

But when I run WD own Tools and did the extensive (long) test on a iMac, it failed to continue at 95%, giving an error message. Not a HD error message, but a tool error message. I run the simple test and the HD passed with flyhing colors. But for some reason I cant find, it failed ALL attempts of a complete scan (takes over 16 hours) because it always fail at 95%.

Again, Id like to point out that on a windows running machine, check disk found no problems on this HDD.

But Western Digital own tool couldnt complete a full scan on a iMac running Mojave.

So, my question is: is this HDD unreliable? Trash can ready? Or there could be annother reason for the test always failling at 95%???

Thansk in advance for any help!!