Bad sectors not detected over USB connection

[raotor]

Hello,

Just been pulling my hair out, confused about what appears to be contradictory results when checking a faulty hard drive.

Running a bad sector scan when the drive is connected via SATA internally results in multiple bad sectors being detected. Fine, that tallies with the read failures I've been experiencing.

OK, so I had another HDD lying around and so popped it into my USB dock, ran the bad sector scan (taking some 17 hours) to determine if this drive is OK to use for my backups. No bad sectors were detected using the software I have. So, I replaced the faulty drive with the new inside my PC and then had read errors again!

Running a scan using the same software on the internally connected drive resulted in a plethora of bad sectors. Scanning the drive again using the USB dock finds no bad sectors.

Hmmm ...

The dock I have also has an E-SATA connector, so playing a hunch I connected the drive again using the dock, but this time via the E-SATA method and voila! bad sectors detected.

So, I can only conclude that drive scanning software, or at least the one I use (AOMEI Partition Assistant professional) for some reason fails to recognize a bad sector when scanning over a USB connection. I had absolutely no idea this was even a thing and have to wonder if this would also apply to those out there running USB external hard drives and blissfully unaware their drive may have bad sectors without knowing it.

Can anyone confirm or deny this finding, please?

 

[m3tavision]

How is the drive formatted?

 

[raotor]

How is the drive formatted?

The drives are formatted using NTFS.

 

[Olha Chycher]

Hi!!!!!
If the drives are formatted with NTFS, it's possible that the software used for scanning may not be able to access all the data on the drive, leading to an incomplete scan and inconsistent results. Also, some software may not be fully compatible with NTFS, and may not be able to accurately detect bad sectors on NTFS-formatted drives. I recommend trying to use a different tool for scanning the drives or performing a low-level format of the drive and then scanning it again to ensure a thorough check for bad sectors.

 

[raotor]

Hi!!!!!
If the drives are formatted with NTFS, it's possible that the software used for scanning may not be able to access all the data on the drive, leading to an incomplete scan and inconsistent results. Also, some software may not be fully compatible with NTFS, and may not be able to accurately detect bad sectors on NTFS-formatted drives. I recommend trying to use a different tool for scanning the drives or performing a low-level format of the drive and then scanning it again to ensure a thorough check for bad sectors.

Thanks for responding. However, if you check my original post, you will note that the software I use is fully capable of detecting bad sectors when the external HDD dock is connected using E-SATA instead of USB. Given the software is designed to deal with NTFS and has multiple advanced options, the only thing preventing bad sectors that do exist on the drive from being detected, is the connection method, not the software.

 

[Olha Chycher]

Thanks for responding. However, if you check my original post, you will note that the software I use is fully capable of detecting bad sectors when the external HDD dock is connected using E-SATA instead of USB. Given the software is designed to deal with NTFS and has multiple advanced options, the only thing preventing bad sectors that do exist on the drive from being detected, is the connection method, not the software.

I apologize. You are correct, the software you are using is capable of detecting bad sectors, the problem may lie in the connection method.

 

[raotor]

I apologize. You are correct, the software you are using is capable of detecting bad sectors, the problem may lie in the connection method.

No need to apologise )

Yes,it's very weird and somewhat troubling. I used another piece of software, Partition Wizard, to try scanning for bad sectors over the USB connected dock, and that also failed to pick up the errors on the disk via that connection method.

If this isn't an issue with my particular dock, then it's troubling that perhaps the USB protocols with respect mass storage is incapable of detecting errors like this.

Incidentally, I am also disturbed by the fact that NTFS under Windows appears to be perfectly fine writing data on regions of a drive with bad sectors. It only throws an error when reading back that file. I find this situation incomprehensible as far as data integrity goes. One can be storing data on a drive that has bad sectors on it and be unaware of this until such time as you actually need to read the file back.

Had I not Opted to verify my backups, I would never have known that those backup images were corrupted until the verify process attempted to read them back. How many people are using backup software without verifying the files created I wonder.