Can files be properly erased from a drive?

Tomtom111 · 02 Aug 2013

So I saw this video: Where Do Deleted Files Go? - YouTube

And wondered if you run the 'clean all' command in diskpart would that properly erase the data on the drive, or does it just make the space appear available in the same way deleting a file does when deleting in Windows? This isn't to help me or anything I was just curious if there is anyway whatsoever to properly erase data without destroying the physical drive.

Thanks for reading.

x BlueRobot · 02 Aug 2013

Clean All completely overwrites the sectors on a hard drive with 0's, making the data very difficult to recover (I'm not sure about impossible), whereas, deleting the file simply hides the file from the file system. The Clean switch just overwrites one sector where the file resides with one 0, simply hiding the file again.

whs · 02 Aug 2013

'Clean All' writes zeros into the space. That does not make the data 100% unrecoverable, but it is a good start. A normal delete only switches a bit in the Master File Table but leaves the data intact.

There are various military strength programs that will do better.

Tomtom111 · 02 Aug 2013

Ok, so the 'clean all' command doesn't rewrite everything to zero as I believed? Would it just corrupt the majority of the files, and then making them worthless? Is there no way to write everything to zero, making it completely unrecoverable?

MilesAhead · 02 Aug 2013

One feature of CCleaner is a deleted file overwrite. It writes 0s and you can set how many times it repeats the process. Likely it's not up to military security requirements. But it's probably good enough for the basic home user.

x BlueRobot · 02 Aug 2013

Tomtom111 said:

Ok, so the 'clean all' command doesn't rewrite everything to zero as I believed? Would it just corrupt the majority of the files, and then making them worthless? Is there no way to write everything to zero, making it completely unrecoverable?

Clean All does rewrite everything to 0's, but this doesn't make it impossible to recover the data. What are you trying to delete?

MilesAhead · 02 Aug 2013

Along with overwriting the file in question one must be cognizant of "previous versions of files" in restore points.

Tomtom111 · 02 Aug 2013

[QUOTE=x BlueRobot;2484664]

Tomtom111 said:

Clean All does rewrite everything to 0's, but this doesn't make it impossible to recover the data. What are you trying to delete?

NOTHING!!! As I said in the first post, this is just about finding out if clean all would actually erase everything on a drive, as it wasn't mentioned in the video I linked.
I'm ignoring previous version in this question and just going on the assumption that there is only one version of every file, even though that would be true in a real world situation.
Is there any public software, ie not military, that completly erases data? Again, I'm not trying to delete anything to that extent, I just want to know to what extent normal home users can delete files.

MilesAhead · 02 Aug 2013

[QUOTE=Tomtom111;2484681]

x BlueRobot said:

Tomtom111 said:

Clean All does rewrite everything to 0's, but this doesn't make it impossible to recover the data. What are you trying to delete?

NOTHING!!! As I said in the first post, this is just about finding out if clean all would actually erase everything on a drive, as it wasn't mentioned in the video I linked.
I'm ignoring previous version in this question and just going on the assumption that there is only one version of every file, even though that would be true in a real world situation.
Is there any public software, ie not military, that completly erases data? Again, I'm not trying to delete anything to that extent, I just want to know to what extent normal home users can delete files.

I don't know how you could determine this other than trial and error. Every drive media, controller and driver is likely to be a bit different. An omnicient guess wouldn't really help you much.

Layback Bear · 02 Aug 2013

How clean is clean? How secure is secure?
It all depends on who is trying to retrieve the information.
For normal use one or maybe two passes with zeros would be more than enough.
The Department of Defense uses seven over wrights.
You could also use the Gutmann's method.

Gutmann method - Wikipedia, the free encyclopedia

Clean All will work quiet well for most of us.

Now if you have something very very special on a hard drive like old files from the KGB I would just through the hard drive in a furnace. Drink some Vodka and watch it turn into a puddle.