[The Juba]

I would like to know if it is possilbe to delete/wipe files from the unallocated clusters. Each time I deep scan my harddrive with PC Tools File Recover it finds thousands of files. I've tried (Eraser) but it doesn't wipe them. I Also tried (CyberScrub) more than once but it also doesn't do the trick. I've turned off the system restore. Can anyone tell me what to do please? thanks a lot.

[lotuseclat79]

Hi The Juba,

Welcome to TSG!

Try SDelete v1.51.

Sdelete: Securely overwrite your sensitive files and cleanse your free space of previously deleted files using this DoD-compliant secure delete program.

SDelete will wipe your free space. Do it from Safe mode from a System Administrator account. Read the documentation before using it.

-- Tom

[JohnWill]

Eraser is another very flexible applications to do this.

[The Juba]

I tried Eraser but it doesn't wipe the files, like I said.

[The Juba]

Thanks for the program Tom.
I tried to reed the manual but it's quite comlicated and the program appears to be very dangerous; i'm afraid that it wipes my intire hard disk or some important files! Have you tried it out?

[lotuseclat79]

Hi The Juba,

Read the manual again, and again, and again until you understand how to use the program in a safe way. Use in in Windows Safe Mode. Ask questions. That is what we are here for in order to help you. Forget your fears, and learn how to use the program by practicing on paper. When you don't understand something - ask a question.

No, I have not used it, but I know its the program you need to run to do what you have asked.

Now, read that documentation, and ask more questions if you don't understand something so we can help you determine the answer to your question, and you can resolve your problem.

-- Tom

[WhitPhil]

Eraser will do what you want to do. It will Erase free space as well as cluster tips.

And, doing anything with System Restore has no affect on this.

Btw, these are not really files, but portions of files that have been previously deleted or overwritten.

Is this a security concern?

[firestormer]

How to use eraser:

Open Eraser
File > New Task
Select Unused Space On Drive
OK

Edit>Preferences>Erasing> Unused Disk Space [TAB]
Select the appropriot options and the strength of erasing (Gutmann being the strongest as it overwrites the data 35 times)
OK

Right click on the Task you have just created and click Run...

You can also erase files in Explore using right click Erase

You can use Rucuva to recover data and to check that the data has been fully erased:
http://www.recuva.com/

[lotuseclat79]

Hi firestormer,

In case you didn't know - Gutmann's previous work applied to older disks - not to more recent modern disks. Here is some information that will bring you up to date on his technique (the best you can do today is 3-7 overwrite passes depending on how paranoid you are):

Gutmann method: Best? No.

Most of the passes in the Gutmann wipe are designed to flip the bits in MFM/RLL encoded disks, which is an encoding that modern hard disks do not use.

In a followup to his paper, Gutmann said that it is unnecessary to run those passes because you cannot be reasonably certain about how a modern hard disk stores data on the platter. If the encoding is unknown, then writing random patterns is your best strategy.

In particular, Gutmann says that "in the time since this paper was published, some people have treated the 35-pass overwrite technique described in it more as a kind of voodoo incantation to banish evil spirits than the result of a technical analysis of drive encoding techniques. As a result, they advocate applying the voodoo to PRML and EPRML drives even though it will have no more effect than a simple scrubbing with random data... For any modern PRML/EPRML drive, a few passes of random scrubbing is the best you can do".

Read these papers by Peter Gutmann:

Secure Deletion of Data from Magnetic and Solid-State Memory

http://www.cs.auckland.ac.nz/~pgut00...ecure-del.html (stale, try wayback.org)
i.e. http://www.wayback.org and plug in the above URL there.

Data Remanence in Semiconductor Devices

http://www.cypherpunks.to/~peter/usenix01.pdf

-- Tom

[firestormer]

Thanks i didn't know that i dont use it anyway cos im not quite that paranoid i usualy only do 2 or 3 passes

[JohnWill]

Originally Posted by The Juba

I tried Eraser but it doesn't wipe the files, like I said.

Perhaps you're not setting the options correctly. It sure says it wipes all free space on the disk, hard to imagine they're lying about that.