Trouble identifying which disk is throwing errors

skyadmin used Ask the Experts™
I am getting an error that \Device\Harddisk3\ is throwing bad blocks.

I am having a hard time determining which disk this is. It says disk 3, but I do not seem to have a disk 3...

See screenshot.
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Diskpart hit enter
select disk 3
detail disk

Edit: Just realizing from your attachment you ran diskpart and did not see a disk.

Do you have any external media attached USB etc ?

Do you have a RAID configuration, its a long shot but maybe IRST(or similar) is saying disk 3 on a raid array is going bad?
Download Hard Disk Sentinel from

It is free to try and will give you health status of each disk, Brand, Model and serial number.

It will help you determine which disk is playing up and what the problem is.
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I do have an external USB disk.. that's whats showing as disk 2 in disk manager.

It is a raid 5...

I will try Hard Disk Sentinel and let you know what I find. Appreciate the feedback.
Open your raid configuration utility and look for errors there, its possible the raid may be headed south.

HDSentinal wont be able to do anything with your raid array. Because it appears as a physical disk to windows and the OS. RAID arrays don't usually report SMART states either. to diagnose the hardware you will need to use the raid utility
Top Expert 2013
it is probably disk 2
several soft count from 0, so this makes the 3rd disk disk 2
others count from 1 (in the bios)
noxchoIT Product Manager
Top Expert 2009

Actually you do not have there so many disks so identifying must be really easy. Run on each disk partition CHKDSK x: and see what the report say. If you have bad block it will let you this know.
But Disk3 in your case is the Disk2.
Top Expert 2013

i even told you why..
Top Expert 2014
It's not necessarily bad blocks, it can show that message when the storage is very busy, see for example (prior to that hotfix the condition was retried without Windows bothering to log an event so unless you're getting other errors you may ignore it. The article at will help identify the command & response (you don't show the details tab in the screenshot).

Since disk0 is valid for the message which must correspond to disk 0 in disk administrator it implies that it is a disk that doesn't exist in your system, that can occur if you're using iSCSI and someone (or some controller) accidentally presents a LUN to you and then masks it off. It does not point to an individual disk in a RAID array.

It is the 3TB Disk Be carefull backup data immediately


This turned out to be an external USB disk. I unplugged it and the errors went away, replugged it and they started occurring again. Our monitoring software has detected this same error for multiple clients, always an external USB device. As such, I think this is safe to ignore, as these devices are only used for backup purposes anyway.


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