How To Remove Bad Sectors Or Bad Clusters From HDD a tutorial for you all

[iGuest 3]

its impossible to remove a bad sector... bad secorts are things like scratches on the surface of the disk make by the read/write head... those heads are razor sharp, and with disks spinning at 7200 rpm, if you give thse disk a good knock, it does some damage...
anyways, the software you pointed out simply maps around the bad sectors. effectivly shrnking the total disk capacity.

bad sectors are of two types. physical bad sectors and data bad sectors. the data bad sectors are removed by writing zeros or with low level format. the physical bad sectors are not possible to remove through software. mostly we come across data bad sectors which are results of corrupted data or virus action. so i think both are correct in their claims. you can try writing zeros by a utility windlg.exe. it is a program which is windows 7 compatible. for physical bad sectors, get a new hard drive.

regards

[yordan 10]

Of course, the difference is purely theoretical.If a low-level format flags a given sector as not to be used by the disk driver, then the bad sector is virtually removed.

[mahesh2k 0]

I am in similar situation with bad sectors and finding all the way I can to remove them or atleast map them to separate from the working file. I have noticed that memtest is starting regularly by linux before startup to check the files and the hd health. So i guess disk is on it's way to going to trash but so far letting me type here and working on it.Most of the forums related to linux and hardware tells you that once they start to appear they rarely go away. If you have blackout or electricity issue then surely you'll catch the bad sectors in future. There is no way to skip them. Just have to use the backup for power and then allow the min 5 toshut down or atleast not shutdown due to electricity fail.I have seen some tools like fsck and other which are run from the command line but they rarely help to remove the bad sectors. If you have got them then i guess you should consider looking for another HD and that way you can simply switch to another hd. Use the bad sector one for testing and random stuff which is not serious work.

[yordan 10]

Have a look for a "low level format tool" (diskpart worked nice some ten years ago). Most of them work under windows, so you will have to put the disk on another system. This will have to be done when you will on the "testing purpose" part of your plan, because low level formatting will destroy all your data, and if the software is bugged it will definitively destroy your hard drive!

[iGuest 3]

HDD Regenerator Rocks I am able to fix bad sectors from 2 hard drives....Now both HD are working perfectly....Also check them through system diagnostic, showed HD test Passed.....It is a simple procedure just use HDD Regenerator software...make bootabe usb/dic and run the software through booting from USB/Dics....Select the option scan and repair..No data will Lose...All bad sectors will b recovered.

[mahesh2k 0]

Is HDD regenerator free or you need to pay for it. I just don't want to pay for the disk tools because system like linux already have most of these tools. As for this paid tool if it is worthy only if it is going be usable on multiple platforms. I am using linux purely with no windows system at all. If this hDD regenerator is going to work only on the windows then it is disadvantage for me.From what you're saying it looks like that they are giving us options to boot into HD in low level write and read mode. That way they are separating the sectors. I am sure it may work in case of the windows. I'll see if i can get my hands on the windows system so that i can get the boot usb or cd and that way i can see if it gets fixed.

[yordan 10]

I If this hDD regenerator is going to work only on the windows then it is disadvantage for me.

Techno007 already answered this :

make bootabe usb/dic and run the software through booting from USB/Dics

Which is an obvious situation. You cannot correctly check the disk where you are booted from. So, you need to have the tool on a bootable CD or USB device. So, the real Operating system is not important, it's embedded on the bootable device, whether your hard disk is Windows or Linux.

[manuleka 0]

bad sectors are of two types. physical bad sectors and data bad sectors. the data bad sectors are removed by writing zeros or with low level format. the physical bad sectors are not possible to remove through software. mostly we come across data bad sectors which are results of corrupted data or virus action. so i think both are correct in their claims. you can try writing zeros by a utility windlg.exe. it is a program which is windows 7 compatible. for physical bad sectors, get a new hard drive.

regards

but physical bad sectors are still fixable right? but most probably more expensive than buying a new drive

[yordan 10]

but physical bad sectors are still fixable right? but most probably more expensive than buying a new drive

No, physical bad sectors are not fixable. A real bad sector is a sector with a physical problem (dust or scratch during manufacturation). The low-level format is in charge of preventing the operating system from using these bad sectors. The initial bad sectors are flagged as "do not use this", and are harmless.
New occurence of a scratch or a dust intering the disk subsystem will lead to a new useless sector, but the operating system does not know that no data should be written on it. So, an extra toos is need for that. Crosoft Windows allows you to perform a disk check and will flag these sectors as unusable, but if you already have data or binary files there, they are lost.

[mahesh2k 0]

Physical bad sectors appear for many reasons llike say power outage, disk damage or disk dropping etc. So if there are sectors under issue due to these reasons they can be mapped out and kept aside but they can't be recovered. I have seen that sometimes few people install linux and windows on such system use it for some days. After that system eventually increases the bad sectors though this time more of recoverable, but eventually there are many and system won't boot up.This is what happens in most worst case scenario cases and for that reason i am not using such HDD. I am sure that there are people who wish to use HDD for time being and for them mapping of the bad sector is quite needed. Window based utilities are quite common because most of the disk manufacturers are supporting the window based installs more than linux. I am trying to find some good linux packages that can help, so that i can use them under liveusb.

[manuleka 0]

No, physical bad sectors are not fixable.

I think they can be fixed, if you take a Western Digital drive physically damaged to WD factory or lab... they should be able to fix it! Although maybe the data wouldn't be retrievable from the damaged area... and the cost would be quite high of course

[mahesh2k 0]

If i am not wrong then the disks that are sent to the western digital or any recovery media are for the data recovery. Once the physical sectors are mapped they don't resale or send the same drive and they usually suggest either buying or replacing the drive with the new one. That is what happened to my seagate drive which was damaged and later given to the company only to get replaced with the new one.

[manuleka 0]

If i am not wrong then the disks that are sent to the western digital or any recovery media are for the data recovery. Once the physical sectors are mapped they don't resale or send the same drive and they usually suggest either buying or replacing the drive with the new one. That is what happened to my seagate drive which was damaged and later given to the company only to get replaced with the new one.

exactly... meaning the cost of it being fixed for reuse is worth more than just getting a new one right? but they can still be fixed though i presume
Edited April 23, 2012 by manuleka (see edit history)

[iGuest 3]

Hope I can shed some light on this topic. If not I will at least provide some interesting references. I listen to the Security Now podcast (https://www.grc.com/securitynow.htm) and one of the hosts is Steve Gibson http://forums.xisto.com/no_longer_exists/) which produces a hard drive utility which I use and recommend called SpinRite (https://www.grc.com/intro.htm). Steve is fairly well know to the tech community from his appearances on the "The Screen Savers" (http://forums.xisto.com/no_longer_exists/) television show and his avid crusade against spyware. This is all going to the point that he knows what he is talking about.
Over the years Steve has talked about the inner workings of hard drives as this is a dear subject to him. Here is what I have gathered from the many discussions about hard drives and bad sectors in particular. Bad sectors are physical defects on the surface of the hard drive and they can't be erased. The best you can do is identify them and move them to a different physical area of the drive. With drives getting to be so large, a certain amount of free space is left intentionally on the platters for this very reason. Modern drives are constantly monitoring the data written and read from the platters via internal checksums (such as CRC or similar checksums). If the drives detects that a sector is about to become unreadable, it internally moves that data to a different physical sector and marks the bad sector to be put out of service.

A side effect of this scheme is that a sector cannot be examined unless it is requested. This means that if you copy a file to the hard drive and then not access it for years (think all of those Windows install files) it has a higher chance to go bad then a regularly accessed file. When a bad sector is accessed, first the hard drive tries to recover the sector internally. If that fails, a message is sent to the operating system stating that the sector is bad.

A scary fact is that most of the raw data read form the platters is bad and has mistakes in it. The checksums and internal recovery mechanisms within modern hard drives are so good that they are able to clean the data and present it to the operating system. If more people understood the inner workings of hard drives, they would certainly back up more.

You've mentioned "Bad sectors are physical defects on the surface of the hard drive and they can't be erased. The best you can do is identify them and move them to a different physical area of the drive.". My question is that if it is a physical defect e.g. in the form of a scratch, then how can it be moved to a different physical location?

[manuleka 0]

You've mentioned "Bad sectors are physical defects on the surface of the hard drive and they can't be erased. The best you can do is identify them and move them to a different physical area of the drive.". My question is that if it is a physical defect e.g. in the form of a scratch, then how can it be moved to a different physical location?

you can't... well some softwares can actually try and retrieve some of the data if it can... otherwise its not available anymore