Can “File Shredder” app shred .zip files/folders?

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When needed, I have been utilizing “File Shredder” to shred files, letters, etc depending on what info they contain.  Lately I have had a need to receive more .zip files.

No problem unzipping, reading/utilizing the file information then deleting the unzipped info, or even simply deleting the .zip file; however getting rid of the actual .zip file itself securely (shredding) is the problem.

How can one “securely” delete the .zip file contents and folder once the info has been extracted?

Windows 11 Pro v24H2 and Windows 10 Pro x64 v22H2

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Tex265 wrote:

How can one “securely” delete the .zip file contents and folder once the info has been extracted?

I use the Free App Eraser. I assumed it would be able to erase .zip files, but to be sure, I did find where it is mentioned.

Files compressed with an external application, such as ZIP files, can naturally be erased.

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A zip file is just a file.
Extracted contents are just files.
A shredder will erase all.

I would encrypt your disk using Bitlocker or Veracrypt, then you don’t need to worry about shredding – it’s what I do.

cheers, Paul

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TechTango

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Veracrypt

I use Veracrypt but only for some file groups/folders.  As an MVP, which is your preference for full drive encryption?

Desktop mobo Asus TUF X299 Mark 1, CPU: Intel Core i7-7820X Skylake-X 8-Core 3.6 GHz, RAM: 32GB, GPU: Nvidia GTX 1050 Ti 4GB. Display: Four 27" 1080p screens 2 over 2 quad.

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TechTango wrote:

which is your preference for full drive encryption?

I would use Bitlocker in W11 on modern hardware – it’s on by default in Windows. (Make sure you have backed up the recovery keys and printed / saved them locally.

I use Veracrypt on my older W10 Home machines because they don’t have BL as a default and I wasn’t willing to spend several hundred on my machines for no benefit.

I see no particular benefit to partial encryption, it makes no discernible difference to your use but makes backup / recovery more complex.

cheers, Paul

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Thanks for the replies, but back to the original question – can you securely delete/erase/shred .zip files?

Paul T wrote:

A zip file is just a file. Extracted contents are just files. A shredder will erase all.

Yes, the extracted contents are easily and securely shredded and erased. However; you are then still left with the original actual .zip file and its contents. Can’t securely erase the .zip file itself, and can’t erase the contents individually because they are still in compressed form.

Can delete the .zip file with normal delete command, but that is not securely erasing the .zip file.

Windows 11 Pro v24H2 and Windows 10 Pro x64 v22H2

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Tex265 wrote:

When needed, I have been utilizing “File Shredder” to shred files, letters, etc depending on what info they contain.

Tex265 wrote:

Can delete the .zip file with normal delete command, but that is not securely erasing the .zip file.

After you do just that (and make sure the file didn’t end up in your Recycle Bin…if it did, then simply empty the Recycle Bin), that space the zip file took up on the drive is now considered unused space by the file system. At this point, simply use the built-in “Disk Wiper” utility that’s within File Shredder…

which uses shredding algorithm to wipe unused disk space.

That’s straight from the File shredder homepage, located here:

https://www.fileshredder.org/

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If you’re referring to the Free File Shredder app, I just verified it can shred compressed files!

As long as what you select is the actual file displayed in the right-hand pane and not the folder displayed in left-hand pane (which isn’t the actual file but simply an explorer “view” of its contents!)

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Bob99

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n0ads wrote:

If you’re referring to the Free File Shredder app, I just verified it can shred compressed files!

Yes, I am.

Dang!  Thanks for discovering that one.

I assume you add it to File Shredder app as a “file” and not as a “folder”?

Thanks for your help.

Windows 11 Pro v24H2 and Windows 10 Pro x64 v22H2

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Tex265 wrote:

I assume you add it to File Shredder app as a “file” and not as a “folder”?

Yes or, if you have the Enable Shell Integration option enabled, simply right-click the file and select Secure Delete Files.

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If you have an SSD there is no guarantee that a file shredder will work.
This is because an SSD never writes to the same location whilst the data still exists. This is why disk manufacturers sometimes provide their own secure delete utilities.

Luckily it’s something you don’t have to worry about because the mechanism used by SSDs guarantees your data will be securely deleted some time after you delete a file – assuming the disk is working correctly and you have not moved the file to the Recycle Bin.

cheers, Paul

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PL1

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Currently running HD disks, but have been considering changing over to SSD’s so tell me more.

Paul T wrote:

This is why disk manufacturers sometimes provide their own secure delete utilities.

Like what should you be looking for?

Paul T wrote:

because the mechanism used by SSDs guarantees your data will be securely deleted some time after you delete a file

What mechanism?  How long is “some time after”?

Paul T wrote:

assuming the disk is working correctly and you have not moved the file to the Recycle Bin

Are you advising to delete folders and files directly with the “delete” button vs sending them to/through the Recycle Bin folder?  Why?

Windows 11 Pro v24H2 and Windows 10 Pro x64 v22H2

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The memory cells used in SSDs need to be empty before you can write to them. To prevent writes taking twice as long, SSDs write the new file data to a different location and then delete the old data later, when the disk is quiet. This is called TRIM. When you delete a file, the cells it used will be TRIMmed when the disk is quiet. This guarantees the data is not recoverable, without the need to securely erase the file.
The downside (if there is one) is that the data remains for a finite time, so the manufacturers provide a secure erase utility to reduce that time to zero.

I am not advocating bypassing the Recycle Bin, unless you want to securely erase a file. In this case, hold Shift down when you select Delete and the file will not go to the RB.
BTW, deleted files are not “put in the RB”, the file index is changed to indicate the file is in the RB. The file itself does not move.

Tex265 wrote:

but have been considering changing over to SSD’s

There is nothing to consider, it’s a no-brainer. If you have the cash, migrate to SSD and enjoy the speeeeeeeed!

cheers, Paul

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Paul T wrote:

I see no particular benefit to partial encryption, it makes no discernible difference to your use but makes backup / recovery more complex.

Thanks for your reply.

I was too vague in my comment “I use Veracrypt but only for some file groups/folders.”

What I do is create an encrypted container on an external drive (not my boot drive). Once populated, I copy the encrypted container file to 1) multiple external drives and 2) Onedrive (files not on my boot drive) for cloud protection.  The container is not on my boot drive, just SATA data drives.  The 36 character password would choke a moose.

Desktop mobo Asus TUF X299 Mark 1, CPU: Intel Core i7-7820X Skylake-X 8-Core 3.6 GHz, RAM: 32GB, GPU: Nvidia GTX 1050 Ti 4GB. Display: Four 27" 1080p screens 2 over 2 quad.

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