TechTool Pro has been around for many years and is a reliable way to see what’s going on inside the case at the hardware level. This virtual stethoscope can test RAM, hard drives, graphics and other Mac subsystems, with detailed hardware tests and reports. It’s important to use the correct version of DiskWarrior which supports your Mac model and operating system.Ī more complete alternative to the Apple HW Test Utility is TechTool Pro. I’ve found the best way to use this tool is to boot a troublesome Mac in FireWire target mode, then run DiskWarrior from a second Mac. This works similarly to Rebuild the Desktop from the Classic Mac OS days but in a much more advanced way. Directory errors ( e.g., file not found), permissions problems, copy problems, systems which won’t boot (flashing question mark at startup), DiskWarrior is the thing I reach for first.

My Go-To utility for disk related problems is DiskWarrior, hands down.

Note that these discs are specific to the machines they shipped with, they will not work with other models. Restart with your restore disk in the optical drive – or Flash drive, for new MacBook Airs – and hold down the D key at startup to boot into the Apple HW Test Utility.

Computer maintenance for mac