Bad Sector

Hard drives contain millions of sectors. Each sector is a small area on its surface or it is the smallest area on the disk where a unit of information is stored. Bad sectors can be defined as, those areas or clusters of data, which are not readable or writable on the hard disk or floppy disk. This lowers the performance of the system.

Generally, basic computers have components as follows:

There are many reasons for the cause of low performance. It can be due to very frequent access on the same portion or cluster i.e., wear and tear, the magnetic weakening of the domain and mechanical faults, head crash, abrupt power shut down etc., Bad sectors spread and data on it is lost if data is not backed up on time. Severe bad sectors cannot be repaired; they should be marked as unreadable.

Types of Bad Sectors:

There are two types of Bad Sectors:

  • Hard Bad Sector: It is caused due to physical damage to the disk surface, exposure to intense heat, head crash etc., Difficult to repair but can be prevented.
  • Soft Bad Sector: It is caused when an error correction code (ECC) found in the sector does not match the content of the sector. Very frequent accessing of portions of disk like FAT, MFT etc., causes wear and tear followed by formation of bad sectors. Can be repaired by overwriting with zeros
  • Bad sectors decrease the storage capacity of the hard disk. Regularly, use windows chkdsk to scan and fix errors and to know if there exists any bad sector in the hard drive.

How do I get to know the presence of Bad Sectors?

For an instance, if you come across an error while playing a movie, game etc., saying, “Error reading from source”, then it requires your attention. If the error lies in reading from a FAT system, it can be easily overcome by rewriting it. The problem is when the error persists even after the reinstallation of operating system. To overcome this, one has to reboot and run scandisk in DOS mode. Let us consider a situation wherein, some directories are missing or lost, in such scenario, run chkdsk and the lost directories should be displayed along with the bad sectors if any.

How to perform Chkdsk

Double click on My Computer → select the disk you want to check → click on properties → Tools → Check now → Start.

Prevention of Bad Sectors

Bad Sectors from Hardware and Software should be prevented by making sure that computer is switched off properly, computer is kept clean, using durable or quality hardware parts, good antivirus, malware, spyware software, head crash prevention, defragmentation-thereby avoiding the accessibility on the same portion etc.,

Related Information

Recover data from bad hard drive
Bad hard drives refers to the hard disk contaning bad sectors. A bad sector is part of hard drive which has been damaged due to several reasons like Operating System crash, file system corruption, power surge etc.If hard drives contains bad sectors, then the data stored in it becomes inaccessible. The best solution to overcome this situation is to opt for recovery software like Remo Recover.

How to recover iso image file
Sometimes when you come across bad sectors in hard drive, the first thing we need to do is to create a disk image of entire hard drive. Disk image usually is a replica of your hard drive or partition. Once disk image is created, we can access lost data easily. Remo Recover is the best data recovery software which itself creates a disk image and restores the data from bad hard drive.

Recover data after disk boot failure
Due to OS crash or bad sectors, you may come across errors like "disk boot failure", "boot disk error" etc. In such scenarios, we should try to repair Operating System. If repairing OS doesn't fix the issue, then we need to reinstall the Operating System. If you forget to create a backup of the data stored on hard drive before reinstalling, the entire data might be lost. Remo Recover helps to restore your data back in such scenarios.