You've seen the new, light as a feather, fast as lightening, laptops and you want one -- but you need to sell your old one, in which you invested HUNDREDS of dollars to help you afford the new one and you don't want anyone to get your personal information from it.
So you think -- I'll do a factory reset and that will wipe everything from the drive and I'll be set! Right?
Contrary to popular opinion, a factory reset does not wipe the drive. What a factory reset really does is reformat the drive. This erases the file and folder headers but does not actually remove their content. It corrupts the headers so that Windows can not "see" them anymore, but the files and folders themselves remain. So much so that any decent data recovery app can retrieve most, if not all, of the erased content. That is because those apps do not rely on Windows to find the files and folders, but instead, know what file and folders headers look like and the better ones are able to reconstruct the file system in its entirety.
Let me illustrate the issue with an example...
A relative of mine recently brought their desktop to me because they lost everything! All their stuff -- was GONE! Years and years of treasured family photos and videos, along with long musical playlists, music, video collections -- all gone. The same was true of dozens of website links and all their browsing history along with their saved accounts and passwords.
I checked the drive and sure enough, Windows could not see anything on their 3TB hard disk. The drive had no partitions on it and was unformatted. So, Windows could not see anything on the drive but this apparently unused 3TB of space.
So, like your drive after reformatting, it looked like it was empty.
But then, one day later, after running what I consider to be the very best data recovery tool out there - I had virtually everything back. Nearly 2TB of data, tens of thousands of files, hundreds of folders and all their user profiles (it was a family PC with several profiles). They opened their browsers, logged into their websites and confirmed all their personal stuff was back -- including their online banking information.
What is the point?
The point is that if I could do that with $50 worth of file recovery tool, so can someone else -- someone who bought your used laptop and will then be in possession of your personal details, including your browsing history, your website logins, and any account and/or password information you saved.
So -- what do to about this -- there are two options:
1) replace the drive. New SATA drives for laptops cost $50 or less. A new one will be BLANK, so there is no risk of data being carried over.
2) actually wipe the drive. With PCs that have SSDs that are soldered, you can't replace them, so you have to actually wipe them. You need to go to one of the premier disk partitioning vendors and buy their product -- the version that comes with files that you can use to create bootable media on USB stick. Typical vendors include: MiniTool, Paragon, EaseUS, and others. Once you have installed their product on a different PC, use the option to create a bootable USB stick. Then boot your laptop from that and follow their directions to wipe the drive -- this will overwrite it with ones and/or zeroes. Depending on the options you choose, could take a long time -- HOURS!
Now, you have a blank drive -- so you need to restore your PC to working condition using HP Recovery Media -- which you can create on your own using HP Cloud Recovery tool. You will need a working PC and a 32GB USB stick to hold the recovery files.
Here is the link: https://support.hp.com/us-en/document/ish_4511095-4511141-16
Boot your laptop from the 32GB USB stick and follow the directions to restore the PC.
When the new owner buys your laptop, there will be NO history on it for them to recover.