How can I permanently delete data from an external hard drive?

This is the process I use: Erasing used drives and eMMC - Parted Magic 2026+ builds, NIST -- ignore the NIST stuff, but the rest applies to end users. Most EHDs do not have bridge boards which take well to ATA firmware commands well. The other issue is with WDs since ~2011 the USB bridge is on the PCB and the SATA/ATA interface is masked under WD Ware or AES encryption on the PCB and it rejects it - the issue with using the ATA commands is that it locks them where you need hdparm to unlock the password as they think it has a PSID that doesn't exist in many cases :-(. If that doesn't work, select Erase menu and select Nwipe and do a single pass wipe (press M and select the single pass wipe). If it does have a PSID and you use the ATA commands, you are screwed as WD doesn’t provide it on EHDs - pray it's on the label! If not, you lost that drive.

Newer PM builds have a safety where you can drop and fail it, but it may not help when the command is literally lost in translation. I wrote this on the 3/26 MD5 era builds without that protection, so I may need to update it further.

If you are comfortable with writing to and booting from USB, you can try ShredOS. As the name kind of says, it's an OS you boot from usb, and is specifically for shredding and writing over a physical storage device. This reduces the probability of any old data being recovered if that's a major concern.

https://github.com/PartialVolume/shredos...

Hey, @kuldeeptech

If it is a good-ol' Hard Disk Drive, grab yourself a magnet and slide it around the top and bottom of the external drive. If it isn't, then that is the end of what I know.