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 JoyShine File Eraser
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 Overview
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A file erasure program for Windows that overwrites file contents
before deleting them.

When you perform a normal file deletion on Windows, in most cases
the management information indicating the file's existence (such
as NTFS MFT entries, directory references, and space allocation
bitmaps) is merely marked as "unused," and the actual data area
is not necessarily overwritten at that moment. This program
overwrites the data region that would be left waiting for reuse
before it deletes the file, making standard recovery difficult.

The default method is a single-pass random overwrite based on the
principles of NIST SP 800-88 Rev.2. In addition, you can select
legacy erasure profiles such as the 7-pass method equivalent to
DoD 5220.22-M ECE, or the 35-pass method published by Peter
Gutmann in 1996.


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 System Requirements
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  Windows 10 / 11 (64-bit)
  No installation required, no administrator privileges required,
  no additional DLLs required.


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 How to Use
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  1. Double-click JoyShine File Eraser.exe to launch.
  2. Drag and drop files or folders into the list area.
  3. Select an erasure algorithm.
     (Default = "Random (1-pass) -- Recommended (NIST SP 800-88 Rev.2)")
  4. Check the "Verify primary stream by reading back from disk"
     option (recommended: ON).
  5. Click [Start].
  If you click [Cancel] during the process, the operation will be
  canceled before the next file begins.

  Selecting Tools -> Wipe Free Space... from the menu lets you
  overwrite and erase the "free space allocatable as a normal
  file" on the volume that contains the specified folder. Areas
  that cannot be accessed through the file system, such as the
  MFT, USN journal, shadow copies, and the hidden physical
  regions inside an SSD, are not covered.


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 Important Limitations (Please Read)
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  This program is intended for overwriting and deleting individual
  files, and it does not guarantee complete media sanitization,
  including SSD/NVMe wear leveling, backups, shadow copies, file
  system journals, and cloud sync history.

  - On SSD and NVMe drives, the host cannot control the physical
    sectors targeted by an overwrite due to wear leveling, so
    host-side overwrites are limited in effectiveness. The program
    shows a warning if it detects such a drive. For reliable
    erasure, ATA / NVMe Sanitize, or full-drive encryption such as
    BitLocker combined with key destruction, is recommended.
  - Alternate Data Streams (ADS) are subject to overwriting, but
    read-back verification is applied to the primary stream only.
  - When multiple hard links exist, the content overwrite affects
    all links (which share the same underlying data), but only
    the dropped link name is deleted.
  - For verification, the program uses mt19937 as the pseudo-
    random number generator, seeded from a cryptographic source.
    The output is statistically strong, but it is not a strict
    CSPRNG.
  - When canceled, files that were in progress may remain on disk
    under their scrambled names.
  - Wipe Free Space targets only the free space that can be
    allocated as a normal file. It does not affect the MFT, USN
    journal, shadow copies, or the hidden physical areas inside
    SSDs. Also, depending on volume conditions, if the size that
    can be allocated at once is smaller than the total free space,
    the remaining free space may be left unwritten.


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Contact / Updates
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(News)
https://lee22.net/#JoyShine_File_Eraser

(Contact / Error reports)
https://lee22.net/contact.html

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