How can I recover data from a computer with a failed OS?
Despite the steadily improving reliability of modern operating systems, they are still not designed to absolute perfection and sooner or later suffer from some technical issues. A system failure may be caused by a hardware malfunction or a software crash and results in the inability of the OS to boot normally: it may constantly reboot and freeze with an error message displayed on the screen or even stop working entirely without any notifications. Though such a problem can usually be solved by reinstalling the OS from scratch, a fresh installation destroys everything stored in the system partition provoking massive loss of user data from the internal hard drive. That being so, all the critical files need to be copied out from the storage before the newly installed OS overwrites them while the crashed operating system will prevent any straightforward access to the content of the drive. Fortunately, there may be a couple of ways to settle things down.
To determine the most appropriate course of action, first and foremost, it is important to find out the nature of the problem occurred:
1. Hard drive failure
Unusual noises from the drive, like clicking or grinding, the messages "Invalid System Disk" or "Please Insert Bootable Media", particularly when the machine doesn't detect the drive, are a sign of a disk failure rather than an OS issue. In this case, it's strongly recommended to carefully eject the drive, pack it into an anti-static bag and take it to data recovery specialists for the examination. Further manipulations with the drive without proper training and equipment may lead to its further damage.
2. Defective hardware
Hardware-related problems frequently cause OS failures as the computer becomes unable to function normally. A faulty power supply provokes an immediate shutdown of a system; a bad processor makes it impossible for the computer to process requests or operate in general; a flawed RAM chip may keep the OS from accessing critical data and cause a “Fatal exception error”. As a rule, the computer informs about these problems on startup using error codes displayed on the screen or BIOS beep codes. In order to decode them, you may refer to the website of the motherboard’s manufacturer. If you suspect any damage to computer's hardware other the failure of the hard disk drive, you should take the storage medium out of the machine and use another computer to recover the lost files.
3. Software issues
If every piece of the computer system’s hardware is intact, the failure has most likely resulted from a software glitch, like a malware infection, improper system shutdown, conflicts between applications, incorrect system update, bad drivers, wrong settings or boot sequence which has led to the corruption of the partition table, master boot record, critical system files or even the entire file system. You may see the prompts, like “Error loading operating system,” “Non-System disk or disk error,” “Invalid partition table,” “NTLDR is missing,” “Your PC ran into a problem and needs to restart,” etc. In this situation, data recovery can be performed on another computer just like in the previous case. However, if removing the drives from the affected machine is impossible or undesirable, for instance, due to the warranty or lack of expertise, you may use UFS Explorer Backup and Emergency Recovery CD to boot the computer in a safe environment and carry out the procedure without disassembling the device.
Last update: August 7, 2019