Hard Drive Repair and Data Recovery

Hard drive is a sensitive device with electrical and mechanical components. Any failure and we can not access the disk. The simplest approach is to replace the drive and restore the data. But this is not always possible. In some cases we will need help from professional hard drive data recovery company. Data recovery services are expensive but the value of the files may justify this cost. Hard drive crash can happen to anybody. Repairing a hard drive is not a simple task. To understand why hard drive repair and data recovery is so expensive you need to know about typical failures and how they are fixed. But this is only the first part. After the drive is operational again we need to recover the data, restore the file system and recover missing files.

Dead or damaged hard drive first needs to be analyzed. Hard disk related problems can be divided into few categories.

Failed Electronics

This is one of common hard drive problems. Hard drive electronics has many functions. It provides the interface to the computer (IDE/ATA, SATA or SCSI), it buffers data, controls the motor, monitors spinning, moves heads, remaps bad sectors, etc. There is one printed circuit board with many electronic components. Each component can contribute to disk problems but usually most failures are related to power components. Power supply, motor driver and head actuator driver are places where most electronic failures happen. Data recovery companies usually try to locate the problem. If it is found then they try to repair the board by replacing failed component. If this still does not solve the problem or the cause of malfunction can not be found they replace the board with the same or equivalent one. For this purpose they have large stock of all popular hard drives. They simply take the board from a working drive and put it on the failed drive. Sometimes it is also necessary to replace the ROM chip. If the problem was in electronics then the drive should now be working.

Failed Heads

Hard drive head is a small and the most sensitive device in the drive. It is consisted of small ferrite core with coil mounted on an arm which is moved by special magnetic motor. The head is the device that actually reads and writes the data. The head hovers few micro meters above the rotating platter but it should never touch it. If the problem is in the head it needs to be replaces. This means that the hard drive needs to be opened. This can only be done in a cleanroom. Typically, class 100 or ISO 5 is required for hard drive repair. If the drive is not opened in a clean environment then this will very likely damage platters and cause bad sectors. Another problem with hard drive heads is their replacement. You can not use ordinary tools because they may be magnetic and can damage the data on the platters. Therefore, special non-magnetic tools (no-contact head change tools) need to be used to remove failed heads and to install new ones.

Failed Motor

A failed spindle motor is also one of common causes of hard drive failure. Older hard disk drive motors used ball bearings but newer disk drives use motors with fluid bearings. The problem can be in the electronics or in the motor itself. To replace the motor all the platters and heads have to be removed first. This is a highly complex operation and in addition to clean room and special tools you also need knowledge and experience.

Broken Firmware

Hard drive firmware is internal system software responsible for internal operations and contains unique data specific for each hard drive. The firmware contains the data about model, serial number, disk size, number of sectors, SMART parameters, data about drive heads, encryption parameters, etc. The firmware is located in the host protected area or hidden protected area (HPA) of the disk. This part of the disk can not be normally be accessed by the operating system. You need special tools to read or write there. Firmware related problems are hard to diagnose. Again, without knowledge, experience and tools you can not fix the problem.

Physical Platter Damage and Bad Sectors

The platter holds the data. This is a glass or aluminum disk with magnetic and protective coating. It has highly polished surface. The hard drive head hovers few microns above the platter and any imperfection can cause physical damage and/or bad sector. A sector becomes bad when it can no longer be read faithfully. The drive firmware will try to read the sector many times and if the reading will fail this sector will be marked as bad and will be remapped. Disk platters are far from perfect so some bad sectors are normal. But if the disks are further damaged this will increase the bad sector count and may lead to hard drive failure.

Hard Drive Repair, Data Recovery Service and Data Recovery Cost

Now it is clear why hard drive repair and data recovery service is not cheap. It requires expensive tools and skilled hard drive experts. Simple hard drive recovery may need only data recovery software and few minutes of work. But data recovery service expert can spend hours trying only to repair a clicking or dead disk, let alone the file recovery.

Because hard drives fail and people don't make backups data recovery companies have plenty of work. To avoid paying for data recovery there is one simple solution: make regular backups.


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