Data recovery after OS failure

Despite constantly improving reliability of operating systems users still sometimes experience operating system failures. Failure of an operating system may occur due to corruption of OS logical structures (caused either by computer viruses or human errors) or damage of a storage on which the OS is installed (caused by hardware failures, system breakdowns, instantaneous power failure resulting in file system structures corruption). Corrupted operating system features inability to boot. The symptoms that the operating system shows will tell about failure causes. A failed operating system will attempt to start and may progress to a certain point, freeze and not boot any further. It may attempt to boot and then stop with a blue screen or error message as well. But if the computer goes to a black screen very quickly with an "Invalid System Disk" or "Please Insert Bootable Media" message, particularly if the machine doesn't report the presence of the hard disk drive, then you're experiencing a failed disk not a failed operating system. In this case it's strongly recommended to take the disk to specialists for their examination and conclusion on possibility to recover lost data.
If you're facing operating system failure problem access to your data can be achieved by either of two possible methods. You may connect the hard drive to another computer in a way described in
How to: Connect IDE/SATA drive to a recovery PC article or use
UFS Explorer Backup and Emergency Recovery CD
to boot your computer. If you open the hard drive and the data on it are intact, you may simply copy your files to a safer data storage. If files have been damaged or lost they can be retrieved with an efficient recovery software. SysDev Laboratories advise to apply UFS Explorer Standard Recovery. The software employs effective mechanisms for search of lost or corrupted files on a failed operating system. Supporting a great variety of operating systems and working with a wide range of file systems the software will be a universal solution for recovery of lost files from any operating system type.