I’ve said it countless times: it’s not a question of if you will lose data, but when. Media, such as hard drives, eventually fails. Or you can make the kind of mistake that results in deleted folders or erased disks. And files can simply get corrupted. There are two things you need to do to ensure you don’t lose data: back up your files regularly, and use software to diagnose and correct problems before they become serious.
Since 1998, Alsoft’s DiskWarrior has been the go-to tool for fixing disk corruption on Macs. It’s been eight years since the last update to DiskWarrior. At the time, I reviewed DiskWarrior 4 and gave it the highest rating, five mice. It has saved my data, and fixed hard drive issues, many times over the years.
DiskWarrior does one thing, and does it well: it optimizes and repairs disk directories, which contain the information that tells your Mac where files are stored on the disks attached to it. If directories become corrupted, you can lose files. While your data may still be on a disk, the Mac is no longer capable of finding it. DiskWarrior works both as preventive medicine—to fix errors before they become serious—and to correct more serious errors and help recover files when things get really bad.
Read the rest of my review on Macworld.