HDD Data Recovery
The loss of information on HDD is a major problem, since hard disk drives (HDD) are of large volume: when HDD is malfunctioning, all the information contained on computer may be lost.
Information loss reasons in HDD may be divided into hardware and software. Hardware reasons include HDD malfunctioning resulting in lack of access to data. In such cases, HDD recovery shall first be performed. When this is done, works on the analysis and extraction of the very information may be performed. Software (logical) damages include information loss cases when HDD is properly functioning, but the access to the data stored on it is lost.
EPOS company performs works on information restoration from HDDs even in the most complicated cases. Professional equipment, unique technology and many years of experience allow us to work with any HDD models: ranging from the most advanced to taken out of production models of any manufacturer: Samsung, Seagate, Western Digital, Fujitsu, Hitachi, Toshiba, HP, IBM, Maxtor, Nikimi, Quantum, etc.
The most common reasons for information loss on HDDs are as follows:
Units damage inside the sealed chamber of HDD
The most common malfunctions that need recovery of information from HDD to be performed with the sealed chamber opening - magnetic head assembly breakdown, engine seizure, and displacement of plates. HDD's sealed chamber opening may only be performed in clean room (special equipped room). If work is performed in improper room, irreversible loss of information may occur. EPOS has Ukraine's only clean room of class 100 to perform works inside the sealed chamber of HDD.
The presence of unreadable and hard to read sections on the magnetic surface of the disk
The range of possible damage causes of the magnetic surface of the disk is rather broad, but the most common of them is abnormal operating conditions. Surface destruction process occurs like an avalanche, therefore, when working with damaged drives, it is important to speed up the process of reading and processing of defective sections. EPOS company has developed special adaptive reading technologies that allow to extract the maximum amount of information from HDDs if magnetic surface is damaged.
HDD's control board (controller) damage
Control board damage is one of the most common malfunctions of HDD. This problem is often linked to power supply circuit failures. In such cases, HDD recovery starts with the replacement of controller to undoubted good HDD with its with subsequent adaptation to HDD's sealed chamber. Piece of the service information of HDD is stored on control board, and these unique adaptive setups shall be transferred to the controller that is being installed. Setups transfer to properly functioning control board is performed by using specialized software and hardware.
Service information damage of the storage drive
The service area of HDD's space contains a number of programs that control over the operation of the HDD. This area is inaccessible to the user. If service information is damaged, HDD may be improperly detected in BIOS or may not be detected at all. In such a case, the access to user data on the storage drive is lost. When working with such drives one shall first recover HDD's data from the service area. For this purpose special equipment is used. It provides access to the service information of HDD at the level of technological commands and allows for the performance of works required to correct it. As soon as HDD recovering is performed, data extraction and its subsequent analysis are carried out.
Access blocking to HDD by using password
Increasingly frequently personal computers, laptops, industrial information storage and processing systems use HDD data access protection by using password. When working with such HDDs, removal or bypass of password is first performed through the use of special hardware or software.
Destruction of disk's logical design
Disk's logical design is a procedure that defines data organization principle, format, and method of physical storage of information. Disk's logical design damage may be the lack of access to disk partitions, reflection of logical volumes as unformatted, disappearance or damage of file system objects. To restore data, exact copy of user's space of disk is first created. This very sector-wise copy is used to analyse the degree of damage of logical design and to perform subsequent recovery of information.
Formatting, re-installation of operational system
Formatting process involves creation (formation) of data access logical designs, such as file system structures. There are two formatting options:
- without user area rerecording (fast) - only service tables are created;
- with user area rerecording - recording of user data storage area is performed along with service tables creation.
Upon formatting completion entire user data storage area is treated by operating system as empty, ready to for information recording, regardless of what was in this storage area before the formatting. Therefore, during the subsequent installation of the operating system, new files and directories are recorded to the user area, which partially or completely rerecords data that were there before the formatting.
When working with HDD with damaged logical design, minimization of the number of possible disk accesses is needed. EPOS Engineers have developed the tool that makes HDD work in read-only mode. This allows us to create exact sector-wise copy of a disk without making any changes to the original. Further analysis and data recovery from HDD are performed from copy only.
Information deletion (accidental or intentional)
When data is deleted by using standard means of the operating system, the data itself physically remain on the storage drive, but in file tables they are marked as deleted. The operating system treats place, where deleted objects were located before, as a free and ready to record information. Therefore, when making subsequent recording on a disk, partial or full rerecording of pre-existing data is possible, which in turn complicates the recovery of deleted files or completely excludes such a possibility.