HDAT2 is free software designed to test, diagnose and repair all types of data storage devices. It supports working with devices with many interfaces such as ATA, ATAPI, SATA, NVMe, SSD, USB and SCSI. Most of the hard disk drives use the ATA or SATA interface.
HDAT2 is actually a DOS program and must be run from a bootable disc. It cannot be run from within Windows. The developers offer various bootable disc options. You can download the ISO disc image and burn it to a blank CD. You can also create a bootable 1.44 MB floppy disk (if someone still uses floppy disks) using the disk creation program they offer.
They also offer Windows version of HDAT2 but it is just for demo purpose. It comes with some data files that show a list of imaginary drives on your system. This DEMO version of HDAT2 should be used first in order to familiarize oneself with this software before using the bootable version.
In the user interface of HDAT2, we see a list of detected storage devices. We can select one of these and it will show another menu which includes functions such as device tests, file system, device data, SMART and various commands.
Novice users should abstain from using this program as it contains some commands such as WIPE which can completely erase the data on a storage device. It should be used only by experts who want to check why a hard disk drive is causing problems so often.
We can examine the SMART data to find whether a storage device (that supports SMART) is working fine or might stop working in near future. It also comes with tools to dump the data from a drive to a file for later examination. In the right hands, HDAT2 is a powerful tool for diagnosing and repair of common storage devices problems.
You can download HDAT2 from https://www.hdat2.com/.