I think the most secure way to delete data is to physically destroy the hard drive. There's no way someone can read it then. Of course, you can't use the drive again, but...
How does formatting a hard drive factor into this? If I have a drive of financial records, social security documents etc that I want to retire - would a format be sufficient or should I also take the steps in this video before disposal?
What Leo forgot to mention is everytime you save a file it gets written to a blank sectors on the hard drive, the old location is marked as free, and with the right software it, the old space where the file was saved, can be recovered. You save that file, say, 25 times it can be written in 25 different places on the hard drive and could be recovered 25 times with the right data recovery software. There is a lot of deleting/erasing software out there and they all work. I like CCleaner as it has a feature where you can wipe the free space on a drive using one of several methods. This program works well with active partitioned drives. When I need to blank a drive and wipe all the data and partitions on a drive I use easeus partition magic, it works in windows or from a boot disk. Both programs work on hard drives and solid state drives.
Nowadays most of people's problems with data being stolen right off a drive happen when they leave their laptop somewhere unattended. If that's not you, then you can rest easy. Format doesn't remove the information from the hard drive. It just specifies the hard drive to be used in a different manner or have an operating system installed onto it. The little 1s and 0s of the data are still present, but they can be overwritten now because the computer doesn't see those pieces of data. If that hard drive was accessed by recovery software, that software could see the data. However, when we talk about risk we have to consider what is reasonably likely to happen. If you format the hard drive and your computer isn't a public computer, it's just for your home use, the risk that someone is going to access your personal information on deleted data from a formatted hard drive is very low. If you take your laptop out in public, then your risk is higher if it gets stolen. But those people stealing it would have to be tech savvy enough to recover data from a formatted hard drive, most thieves are not interested in the data, just the machine. If you're already using the hard drive for something else then I wouldn't bother. If the hard drive is totally clean and nothing is on it yet, and you want to make sure, then I would do CMD > Run as Administrator> Leo's command line shown here.
When selling, gifting or even "recycling" (=non-destructive) a device: what kind of delete is "good enough"? Does it make a difference if the Windows drive used BitLocker? What with mobile devices (SSD, non-Windows)?
If you give an old machine to somebody, replace the hard drive. They're cheap, and it's an easy upgrade. There's no reason to leave an old drive in it.
sdelete has a "-c" option, to clean free space. It also has a "-z" option, to zero free space. I have not been able to determine how they differ. The "-z" option has something to do with virtual disk optimization. What that is, and where to run it... I have no idea. Anyone know?
cleaning free space writes random data, which theoritically makes advanced forensics that much more difficult. Zeroing means the data is compressible, allowing virtual disks to be smaller.
@@askleonotenboom So I would run "sdelete -z somefiles", where "somefile" are the actual files of the virtual machine? If yes, I still do not understand what actually happens to those now compressed files? How will my virtual machine software handle those files that have been altered?
@@NoEgg4u You would use -z on files WITHIN the virtual machine or virtual disk. That, then, would allow the physical representation of that virtual disk to be more compressable.
Simple answer is yes. Any writing to an SSD will reduce its life. Look for the TBW value in the specification for the drive. A smaller drive may have a value of 300 (Terabytes written) and a lrge may have 1200 or higher. In real life, does wiping matter? It depends on how often, and how much data (and what drive you're using).
Most likely its this is not even necessary or helpful with an SSD since once a block is trimmed it won't be read back using normal methods. This is the reason why recovering deleted data from SSDs is unlikely at best. For a hard drive the answer is totally different as the data is usually retained after deleting.
The only secure method to permanently delete a file is as follows. First you delete the file, then you burn the hard drive on the microwave oven and finally you shot the drive 10 times. Doing this, your data may not be recoverable.
✅ Watch next ▶ Where Do Deleted Files Go? ▶ th-cam.com/video/dcfI0QnwuBM/w-d-xo.html
You make things so clear that even a 72 year old can follow you! Thanks, Leo!
Agree! And an 81 year old also. Thanks again Leo. JimE
@@JimE6243 At age 75, I'm in the middle, somewhere! 😁
Thanks! (67 here. On the outside, at least. Inside varies from feeling 13 to ~40. :-) ).
why would a 72yo even need a computer
@@thethinkingman- That's a pretty agist comment. TONS of folks use them daily for SO MANY things. You might want to open your eyes.
I think the most secure way to delete data is to physically destroy the hard drive. There's no way someone can read it then. Of course, you can't use the drive again, but...
Agreed I have 5 old drives waiting to be targets on the gun range 😊
But climbing Mt. Doom each time is a drag.
Really great explanation Leo, thank you! A very complex topic really easily explained by Leo
How does formatting a hard drive factor into this? If I have a drive of financial records, social security documents etc that I want to retire - would a format be sufficient or should I also take the steps in this video before disposal?
What Leo forgot to mention is everytime you save a file it gets written to a blank sectors on the hard drive, the old location is marked as free, and with the right software it, the old space where the file was saved, can be recovered. You save that file, say, 25 times it can be written in 25 different places on the hard drive and could be recovered 25 times with the right data recovery software. There is a lot of deleting/erasing software out there and they all work. I like CCleaner as it has a feature where you can wipe the free space on a drive using one of several methods. This program works well with active partitioned drives. When I need to blank a drive and wipe all the data and partitions on a drive I use easeus partition magic, it works in windows or from a boot disk. Both programs work on hard drives and solid state drives.
Nowadays most of people's problems with data being stolen right off a drive happen when they leave their laptop somewhere unattended. If that's not you, then you can rest easy. Format doesn't remove the information from the hard drive. It just specifies the hard drive to be used in a different manner or have an operating system installed onto it. The little 1s and 0s of the data are still present, but they can be overwritten now because the computer doesn't see those pieces of data. If that hard drive was accessed by recovery software, that software could see the data. However, when we talk about risk we have to consider what is reasonably likely to happen. If you format the hard drive and your computer isn't a public computer, it's just for your home use, the risk that someone is going to access your personal information on deleted data from a formatted hard drive is very low. If you take your laptop out in public, then your risk is higher if it gets stolen. But those people stealing it would have to be tech savvy enough to recover data from a formatted hard drive, most thieves are not interested in the data, just the machine. If you're already using the hard drive for something else then I wouldn't bother. If the hard drive is totally clean and nothing is on it yet, and you want to make sure, then I would do CMD > Run as Administrator> Leo's command line shown here.
A "quick" format is NOT sufficient. A full format (takes longer) is typically enough, unless you are in situations outlined in the video.
@@askleonotenboom Thanks :)
I just became very familiar with secure delete last weekend while attempting to wipe a linux boot partition on a disk from a windows machine lol
Right….you were wiping the wrong OS.
When selling, gifting or even "recycling" (=non-destructive) a device: what kind of delete is "good enough"? Does it make a difference if the Windows drive used BitLocker? What with mobile devices (SSD, non-Windows)?
Bitlocker's great. Throw away the key/password.
If you give an old machine to somebody, replace the hard drive. They're cheap, and it's an easy upgrade. There's no reason to leave an old drive in it.
What about deleting data multiple times on an SSD with TRIM enabled? Would that be pointless?
Do a secure delete with gui exist for ssd exist ?
When you format a drive (not quick format) does that do a good job of deleting all files so they are not recoverable?
It is sufficient for most folks, yes. Unless you're NSA's target, for example.
sdelete has a "-c" option, to clean free space. It also has a "-z" option, to zero free space.
I have not been able to determine how they differ.
The "-z" option has something to do with virtual disk optimization. What that is, and where to run it... I have no idea.
Anyone know?
cleaning free space writes random data, which theoritically makes advanced forensics that much more difficult. Zeroing means the data is compressible, allowing virtual disks to be smaller.
@@askleonotenboom So I would run "sdelete -z somefiles", where "somefile" are the actual files of the virtual machine?
If yes, I still do not understand what actually happens to those now compressed files? How will my virtual machine software handle those files that have been altered?
@@NoEgg4u You would use -z on files WITHIN the virtual machine or virtual disk. That, then, would allow the physical representation of that virtual disk to be more compressable.
Will using the wipe free space through CCleaner shorten the lifespan of a SSD?
Simple answer is yes. Any writing to an SSD will reduce its life. Look for the TBW value in the specification for the drive. A smaller drive may have a value of 300 (Terabytes written) and a lrge may have 1200 or higher.
In real life, does wiping matter? It depends on how often, and how much data (and what drive you're using).
Most likely its this is not even necessary or helpful with an SSD since once a block is trimmed it won't be read back using normal methods. This is the reason why recovering deleted data from SSDs is unlikely at best. For a hard drive the answer is totally different as the data is usually retained after deleting.
@@mikaele2x thanks for the info.
@@drescherjm Thanks for the info.
Encrypt the entire Hard Drive or SSD and then delete the Encryption Key.
The only secure method to permanently delete a file is as follows. First you delete the file, then you burn the hard drive on the microwave oven and finally you shot the drive 10 times. Doing this, your data may not be recoverable.
May.
My stuff gets whiped 35 times.
Any Federal employees here?🤣🤣🤣