Safe to give away a formatted computer with Win 7?

[sevenuser9]

I recently bought a new computer with Windows 10 and I want to give away my old Windows 7 computer.

I wanted to wipe my personal data from the Windows 7 computer and so I did a clean install of Win 7. From what I can tell, that cleared everything. My only question is if I give the computer away to a stranger, do they have a way to recover my old data somehow?

 

[FreeBooter]

Erase hard drives with a Darik's Boot and Nuke (DBAN).


Data Removal: Darik's Boot and Nuke - DBAN

 

[sevenuser9]

So the answer is no? A clean install doesn't do this?

 

[Bree]

I recently bought a new computer with Windows 10 and I want to give away my old Windows 7 computer.

I wanted to wipe my personal data from the Windows 7 computer and so I did a clean install of Win 7. From what I can tell, that cleared everything. My only question is if I give the computer away to a stranger, do they have a way to recover my old data somehow?

Welcome to Seven Forums (if only briefly )

Did you know you can still upgrade from W7 to W10 for free? See the link at the top of every page.

If this is an HDD then it is theoretically possible to recover data from unused sectors of the drive. To be safe you could either wipe the unused space...

Cipher Command - Overwrite Deleted Data in Windows

...or boot to a command prompt with your W7 install media, use the Diskpart CLEAN ALL command to wipe the entire HDD, then reinstall W7.

Disk - Clean and Clean All with Diskpart Command


NB: neither of these should be used if the drive is an SSD, that many writes would reduce its life expectancy. Anyway, it's more difficult to recover deleted data from an SSD.

 

[Bree]

So the answer is no? A clean install doesn't do this?

No, a clean install will only overwrite the sectors for the files it copies to the drive. The rest of the sectors will be marked as unused, but will still contain their original data.

 

[Megahertz07]

On the unused space there is still data that can be recovered. On this unused space you should run a drive wiper.
CCleaner has it under Tools - Drive wiper. Select the drive and select Free space only.


PS. You should keep the Win 7 computer for a while. Win 10 isn't that marvelous OS and you may miss Win 7.

 

[NoN]

You even can wipe free space while using your drive as OS with the CCleaner function. I'm used to do it once in a while on all my drives and removal usb sticks.

Never let a drive for sale without wiping the data, for sure. The problem if you're are in a hurry, it will take some times to do it on large ones.

 

[Golden]

This is another approach you may like to consider:
Windows 7 Installation - Prepare PC to be Sold

It uses many of the suggestions posted earlier.

 

[sevenuser9]

Thanks for the replies. It seems to me that we are putting faith in 3rd party software..how does one truly know if the data is gone or not?


The easier thing might be for me to encrypt the drive and bring it to a place that recycles computers so that it's unusable.


I would have thought that a clean install of Windows was a pretty safe bet for wiping the computer. When I went through this process in Windows, I even got a warning saying something to the effect of "this will remove everything".

 

[Golden]

DISKPART and CIPHER are built in Windows commands - they aren't 3rd party software.

 

[FreeBooter]

How to Use Cipher Command to Overwrite Deleted Data in Windows | Tutorials

 

[Megahertz07]

Thanks for the replies. It seems to me that we are putting faith in 3rd party software..how does one truly know if the data is gone or not?


The easier thing might be for me to encrypt the drive and bring it to a place that recycles computers so that it's unusable.


I would have thought that a clean install of Windows was a pretty safe bet for wiping the computer. When I went through this process in Windows, I even got a warning saying something to the effect of "this will remove everything".

You're making it complicate.
CCleaner is a small and free program. And it will do the job
CClener has it under Tools - Drive wiper. Select the drive and select Free space only.

 

[SIW2]

do they have a way to recover my old data somehow?

Yes, unless you overwrite it. Plenty of programs can do that overwriting with various combinations of 0 and 1. There are also some programs that offer “Secure Erase SSD" or similar wording. Allegedly they prevent data recovery.

Or you could use diskpart clean all command, which writes 0 to every sector

 

[RolandJS]

I vote for letting ccleaner or anything similar do a one pass zero-fill of all unused byte-space.
I recommend leaving computer alone, minimal background/foreground activity during free-space wipe.

 

[sevenuser9]

I took the suggestions on here and I'm currently wiping free space only using CCleaner.

So far these are the steps that I took to ensure nobody can access the drive/old data:

1. Installed clean version of Windows 7
2. Installed VeraCrypt encryption software (requires password at boot screen)
3. Used CCleaner to wipe old files saved on the registry

What is the best way to ensure that CCleaner did the job properly? i.e. Should I try using Recuva to see if it can recover any old files? And is one pass enough with CCleaner? I notice multiple passes can be done, but I'm wondering if it is necessary or not.

 

[Bree]

What is the best way to ensure that CCleaner did the job properly? i.e. Should I try using Recuva to see if it can recover any old files? And is one pass enough with CCleaner? I notice multiple passes can be done, but I'm wondering if it is necessary or not.

Yes, try Recuva. You may find a lot of files to recover but they'll only be the 'all zeros' ones CCleaner wrote to the free space.


One pass is enough for any normal recovery process. Multiple passes are only advised if you want to protect against forensic recovery techniques, too difficult/expensive for the average user to employ.

 

[Megahertz07]

Cleaning the empty space is all you need to be sure no one will retrieve your data.
Encryption doesn't do anything to protect from recovering data. The new owner will need to format the drive and reinstall Win 7 and it will be in the same point as you were before you encrypted.

Remove VeraCrypt encryption software and give it to someone who needs a computer. Your data is already safe.

 

[sevenuser9]

I took most people's advice on here and ran CCleaner's Drive Wiper tool. I then wanted to make sure that CCleaner actually did its job and so I ran Recuva afterwards. To my surprise (and disappointment), Recuva was able to recover 5 copies of my old resume along with a bunch of other images and PDFs that I had downloaded - with personal information! Even images that were labeled "000X" were recoverable.

I'm now looking for other solutions given that CCleaner is not foolproof.

 

[Bree]

I'm now looking for other solutions given that CCleaner is not foolproof.

If you are prepared to reinstall W7 from scratch again, then boot from the install disk to a command prompt.

Command Prompt at Startup

Then use Diskpart's CLEAN ALL command to write zeros to every sector before you reinstall W7.

You could use the clean all command (secure erase) to ... have each and every disk sector on the HDD written over and zeroed out completely to securely delete all data on the disk to help prevent the data from being able to be recovered. "Clean All" takes about an hour per 320 GB to finish running.

Disk - Clean and Clean All with Diskpart Command

 

[SIW2]

You could look at aomei ssd secure erase. Part of aomei partition assistant. It claims to be less wearing on the disk.

SSD Secure Erase Utility Restore SSD Advanced Performance without Harming SSD Physical Structure

You might need the pro version - there is a free giveaway at the moment

AOMEI PART ASSIST PRO