It is an old Windows 10 PC and it still worth about $400. 5600G + 32GB RAM + 500GB SSD.
I already made a full backup of entire device and want to completely wipe this pc so I can sell it to someone without worrying about the data leak. How can I do that? i heard a factory reset is not safe and the deleted data can be recovered.
If you wanna sell it with windows, you can use a third party tool to wipe the drive(s) completely and reinstall it. donât forget to login to Microsoft and mark the machine as sold to remove it from your account.
Without windows, after wiping it, reset the TPM settings in uefi/ bios. Watch so next persons installation does not take other identifiers and grabs the license (login to Microsoft and watch it). I would say in a different world that Microsoft has a proper write upâŚ. But I doubt it.
For safe wipe, you need a dedicated disk wiping tool. The factory reset is not enough as far as I know. You need to boot into PE and wipe the whole disk permanently.
+1 Since you have completed the full backup, to completely wipe a PC and ensure that it is permanently lost, I recommend using the âReset This PCâ feature that built into Windows 10 .
Go to Settings > Update & Security > Recovery, and then select the âDelete everythingâ option.
Be sure to check the âClean the drive completelyâ option When the system asks, as this will overwrite the data rather than just performing a quick formatting. Then you are able to completely wipe a PC. This will take a couple of hours but makes it much harder for anyone to recover your old files.
Most importantly, you donât want your SSD contents to be restoreable. The easiest way to get rid of them is to take a Linux installer or rescue system, and unmap the entire drive:
lsblk followed by Enternvme0n1 but depending on how old it is, it might be sdablkdiscard -f /dev/nvme0n1 followed by Enter (make sure to use the correct device name as discovered above)After this procedure, any previous SSD contents will be irrecoverable with means available to regular users (a specialized data recovery company may have means to recover data but I dare think you donât need to worry about that).
Furthermore, as described by other posters, reset your BIOS to defaults, reset the Secure Boot keys to defaults, clear the TPM and fingerprint sensor, and if you plan on using the Windows license after selling the computer, youâll have to remove that as well (there are tools for that). After that, perhaps install a clean copy of Windows in evaluation mode, and itâs ready for sale.
EDIT: 4th bullet point was incorrect.
Using the official Windows installation media is a built-in method to permanently wipe a Windows 10 pc, but it requires a bootable USB drive and will completely delete all local files, so you wonât be able to recover any data.
How to Permanently wipe a Windows 10 PC
Official system tools can completely erase all content on a disk at the partition level; this is the native method for erasing data when you plan to sell or recycle your device.
Since you have an SSD (not a mechanical HDD) on PC, the âoverwrite 7 timesâ method (like DBAN) not only doesnât work well but also shortens the lifespan of the hard drive.
To completely wipe a PC, the built-in Windows âReset this PCâ only does a quick format, but the personal files can still be recovered with tools.
The most correct and efficient method is to use the âsecure eraseâ command built into the SSD. In this way, you can instantly reset all cells to an empty state. It takes less than 1 minute and completely wipe a PC without any recovery.
How do you completely wipe a PC. Many modern motherboards have built-in secure erase functionality in the BIOS.
-After restarting, press the Del or F2 key to enter the BIOS.
-Look for âSecure Eraseâ under the âToolsâ or âPeripheralsâ menu.
-Select your solid-state drive and run it.
If fails. You can use the DiskPart from the command line to completely wipe a PC. The clean all command performs the same zero-fill process as the Windows reset. This is a very powerful method and is suitable for disk disposal.
This Is the correct way.
Since the drive is an SSD, the overwrite method (such as when wiping a HDD) is bad for the SSD. The two mediums work differently
Adding write cycles to an SSD only makes it worse.
But clearing the sending the blk command tells the SSD that area is to be written over.
So When you reinstall windows, itâll likely be written over and youâre fine.
Could always use DBAN
If you want to absolutely wipe all data from drives, I recommend ShredOS. Itâs a bootable ISO (make a Ventoy USB-stick and chuck the ISO on there), super easy to use.
And as for wiping, you donât need to do a 37-pass DoD-wipe.. Even a âall ones > random > all zeroesâ wipe is plenty good enough.
If you want to sell with Windows installed, just reinstall Windows and select the âIâm selling my PC, please wipe it properlyâ option during install. 
Since it has an SSD, I would not rely only on a normal factory reset.
The safest practical method is to use the SSD manufacturerâs secure erase tool, or the Secure Erase/Sanitize option in the motherboard BIOS if it has one. After that, reinstall Windows 10 from a USB installer and stop at the initial setup screen so the buyer can finish it.
If BitLocker was enabled, that also helps because wiping the drive removes access to the encryption key. I would still use Secure Erase before selling it.
Or you could just buy a cheap ssd and replace it with the current one.
Then you know for sure they cannot access any data.
And you could add a few pennies to the asking price. 
That blkdiscard command sounds quite handy. Iâm not expecting to ever sell off a system with a SSD/NVMe in it (once PC hardware arrives at my house, it never leaves until itâs dead [1]). But for re-using a solid-state drive at home I may want to try it.
[1] when a HDD dies here I usually dismantle it and scatter the parts, keeping the magnets. A SSD or NVMe simply needs to meet Mr Sledgehammer.
The last one I did, was 2 sas drives in a mirror. I used the secure erase on it. Then I broke the mirror and set it up as raid 0, then ran the secure erase again. Reset up the mirror and installed debian on it. I felt confident no one could access any thing from the original red hat install.
Next time you need to secure-erase something, donât erase the array-device, just erase the underlying physical devices and be done with it.
No need to wipe the array, create another array on the devices, erase that, then recreate yet another array and install something there. Thatâs just extra steps that do nothing that couldnât be done with an extra round of writing zeros to diskâŚ
If you are planning to sell your Windows 10 PC, I would recommend securely erasing the SSD instead of relying only on deleting files or performing a normal factory reset.
You can try these options:
Windows Reset: Go to Settings > Update & Security > Recovery > Reset this PC. Select Remove everything and enable the Clean data option if available.
SSD Secure Erase: Check whether your SSD manufacturer provides a Secure Erase or Sanitize utility. This is a better option for permanently removing data from an SSD.
Data Wipe Software: You can also use a dedicated data wiping tool to erase the drive before selling your computer.
I would also suggest checking out SysTools Data Wipe Software. It provides different data wiping methods to erase drives and help prevent recovery of previously stored information.
One important point: SSDs work differently from traditional HDDs, so avoid repeatedly overwriting an SSD with multiple passes. Use the SSD manufacturerâs recommended Secure Erase or Sanitize method.
After wiping the drive, you can reinstall Windows so the new owner can set up the PC.
Agree with this. SSDâs only need to be written over once to delete the data. Restoring Windows, reset tmp keys, wipe free space single pass which shouldnât take long, done.
Secure Erase is a feature built into every HDD and SSD since 2001.
Secure Erase is a NIST standard that is equivalent to physical destruction.
No information is recoverable, no headers, no metadata, no bad blocks, no hidden partitionsâŚ100% wipe.
The easiest way to access the Secure Erase feature is using: hdparm
# hdparm -I /dev/X
(Replace /dev/X with /dev/sdx: Use âfdisk -lâ to see what theyâre named.)
This will check to see what state the drive is in.
It will say âfrozenâ or ânot frozenâ. If ânot frozenâ then you can proceed with the directions for setting a password and executing Secure Erase.
If it says âFrozenâ you can check the Bios to see if you can change the âfrozenâ state. If notâŚ
Then you have to âhot replugâ if that feature is supported. After first booting into linux, unplug and replug in the HDD. This will change the state from âfrozenâ to ânot frozenâ.
READ about your drives features, is hot replugging possible?
NVMEâs require power to be disabled before unplugging the drives. Know your drive technology.
I have not personally used Secure Erase on any NVME drives so I donât know if it will work on them. With a little research it shouldnât be too difficult to determine if it will.
The easiest way to use âhdparmâ is with a linux iso on a flash drive. Not all linux distroâs include hdparm by default, because itâs a very powerful low level tool that can be a foot gun.
Ubuntu 10.10 iso has âhdparmâ without the need to update and download as in other isoâs. Many distroâs stopped shipping with âhdparmâ after this point in Linux. (Fedtards didnât like people being able to nuke their drives. They attacked the kernel.org ata wiki deleting the secure erase entry and had distroâs remove âhdparmâ from the isoâs. Fun days.)
I think all these good suggestions of using an separate, external OS to wipe the drive securely, preferable using secure erase, are great ideas, but please do bear in mind, that almost all people buying a computer, will need an ooerstingsystem installed on it.
I would suggest letting the license go, but removing the device from your list on the Microsoft account, and letting the next person, use the license, after you have recovered your personal data from it.
Or, buying a fresh license, and providing it with the machine for the next person, with instructions of how you register/set it.
Unless you specifically check with the buyer, that they themselves can source a copy of windows and install it