asusfan

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As the title says, I am curious about the difference between shredding and maxing out the space of HD, flash drive, and other storage devices using Windows 7 and above.

When I shred files, of course the files are hopefully unrecoverable or at least mostly. I hear that this is because the empty space keeps traces of the files.

What if I fill up the device to capacity? Would I still need to shred deleted files for extra security even though there is no space or a minute number of bytes left.

For example, a storage device's empty space contains years of trash bin deleted files. Instead of running a long empty space shred on the large capacity device, I'd like to fill it up with large video files and then shred the empty space, which again is extremely small. Then, just delete the video files normally and repeat the process.

Can this help prevent file recovery? I assume that if the device is full to capacity or almost full that the old deleted files would be unrecoverable. Or am I mistaken? Is there some way to recover files even when the empty space has been filled up?

Any clarity would be appreciated!
 
Solution
If you fill up the storage device, previously "deleted" files will be overwritten and not recoverable by normal means. When you delete a file, it is not actually physically erased from the storage device. The operating system just knows that it is OK to use that space on the storage device for new files when it needs the space, so eventually the old file will be overwritten. If the old file was written to several places on the storage device (not contiguous) then it will theoretically take longer to completely overwrite the complete file. I am not sure exactly how SSD's store files, but I think by design, they do not store files contiguously in one area of the device.

By the way, you should not attempt to completely fill any...

mbarnes86

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Sep 16, 2010
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Hi

Simply shredding a file does not destroy any copies made then deleted

Heidies eraser and ccleane can wipe unused space
A full and slow format with vista or later is just as good in most cases

There is a program h2testw designed to fill usb memory sticks to confirm capacity which can also test and erase free space on hdd

Only one pass is needed , the multie pass erase is not needed on modern hard drives

There is the posibility of parts of a file being recovered unless the option to remove the tips of files is ticked in ccleaner and eraser
If a file is not exactly a sector long eg 512 or 4096 bytes when a file is written it may not overwrite the whole sector
This takes longer to do as all sectors on the hdd have to be written

For ssd things get much more complicated and above may not apply

One of my friends is paranoid and after erasing his old hard drives he puts a blowlamp on it until it melts then even the cia or nsa can not recover anything

Regards
Mike Barnes
 

mjslakeridge

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Why are you wanting to erase the HDD, are you going to sell the computer (or HDD)? I have a program named Acronis True Image Home that is used to make backups, but also has a feature to triple write over the entire drive, ensuring that all traces of the data is gone (supposedly). I don't know if there is a free version, maybe the programs Mike Barnes recommended are?
 

asusfan

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Feb 7, 2014
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Hi. I appreciate the replies. My main concern is how easily deleted files can be recovered if I fill up the storage device (original Q).

And if files can still easily (not by gov't agents or high-level hackers but every day programs) be recovered, why is this so since the storage device has almost 0b remaining. I would assume that all files would be destroyed this way. Unless they are saved somewhere else also in secret areas?

Is there any opinion on this?
 

mjslakeridge

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If you fill up the storage device, previously "deleted" files will be overwritten and not recoverable by normal means. When you delete a file, it is not actually physically erased from the storage device. The operating system just knows that it is OK to use that space on the storage device for new files when it needs the space, so eventually the old file will be overwritten. If the old file was written to several places on the storage device (not contiguous) then it will theoretically take longer to completely overwrite the complete file. I am not sure exactly how SSD's store files, but I think by design, they do not store files contiguously in one area of the device.

By the way, you should not attempt to completely fill any storage device, as it will affect the read/write performance of the device. I think the rule of thumb for SSDs is about 80-85% (maybe that has changed for newer SSDs).
 
Solution

asusfan

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Feb 7, 2014
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Thanks for the additional info. That is a good point about the file being spread out on the device. OK, I'll be more specific to make it easier. Let's say my internal IDE notebook NTFS or FAT32 HD, 320GB. I only use these formats. Hopefully USB flash drives work the same way for my question.

The one in question has 4 partitions, two of them are locked and contain the recovery files that came with the PC. I have C and D partitions. The C drive is fine as is. Regarding just the D partition:

1) When I delete a file from the D partition, can it be spread out to the other partitions (non D) as well since it is one HD or will it remain on just the D. Meaning, if I wipe or fill up the D, might there be traces on the C drive, other parts or the locked backup parts of the HD?

2) Just to reconfirm, filling up the D partition (not the OS C) to less than 1KB is not recommended even if it is just as a temp transfer/delete process? Can this actually damage the HD if I just do it a few times or do you mean that it affects performance while it is full? I would only transfer the files to fill it and then delete it immediately. Not leave them there.
 

mjslakeridge

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With respect to your question #1, I am not sure, but I think once you set up partitions, and write to the D partition, then only the D partition will contain that data (someone correct me if that is wrong).

Question #2, you won't damage the HD if you fill up a partition, it may just affect the performance while it is full. Once you "delete" the files, that space is now available to be overwritten with new data.