DeDRM not working with latest KFX-ZIP files from Kindle

[dlinnenbruegger-ops]

I get an error message with latest file dlownloads KFX ZIP from my Kindle.
"This fileis locked by DRM. To learn more about...."
Older KFX files work fine. Any idea?
Using Calibre 8.9
DeDRM 10.0.9

[ElleKayEm]

Post a debug log of adding the book.

[dlinnenbruegger-ops]

calibre 8.9 embedded-python: True
macOS-15.6.1-arm64-arm-64bit Darwin ('64bit', '')
('Darwin', '24.6.0', 'Darwin Kernel Version 24.6.0: Mon Jul 14 11:30:55 PDT 2025; root:xnu-11417.140.69~1/RELEASE_ARM64_T6031')
Python 3.11.12
OSX: ('15.6.1', ('', '', ''), 'arm64')
Interface language: de
EXE path: /Applications/calibre.app/Contents/MacOS/calibre-debug
Successfully initialized third party plugins: Gather KFX-ZIP (from KFX Input) (2, 26, 2) && DeDRM (10, 0, 9) && Package KFX (from KFX Input) (2, 26, 2) && Access Aide (0, 1, 15) && KFX metadata reader (from KFX Input) (2, 26, 2) && From KFX (2, 26, 2) && KFX Input (2, 26, 2) && Set KFX metadata (from KFX Output) (2, 17, 1) && KFX Output (2, 17, 1)
QPA platform: cocoa
devicePixelRatio: 2.0
logicalDpi: 72.0 x 72.0
physicalDpi: 81.5000012240072 x 83.00000124653495
ApplicationPaletteChange event ignored
Using calibre Qt style: True
[0.00] Starting up...
[0.02] Showing splash screen...
[1.18] splash screen shown
[1.18] Initializing db...
[1.19] db initialized
[1.19] Constructing main UI...
qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
[1.68] GUI main window shown
[1.70] main UI initialized...
[1.70] Hiding splash screen
[1.74] splash screen hidden
[1.74] Started up in 1.74 seconds with 5 books
QDesktopServices::openUrl() failed for url: PyQt6.QtCore.QUrl('file:///Users/dirklinnenbruegger/Calibre-Bibliothek/Reinhard K. Sprenger/Radikal fuhren (9)/Radikal fuhren - Reinhard K. Sprenger.kfx-zip')
Failed to request permission for showing notification: The operation couldn’t be completed. (UNErrorDomain error 1.)
Worker Launch took: 0.01 seconds
Job: 0 Buch 1 von 1 (Radikal führen) konvertieren finished
Buch 1 von 1 (Radikal führen) konvertieren
DeDRM v10.0.9: Trying to decrypt c8vbpth0.kfx-zip
Decrypting KFX-ZIP ebook: c8vbpth0
Found 1 keys to try after 0.3 seconds
DeDRM v10.0.9: Failed to decrypt with error: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher
DeDRM v10.0.9: Looking for new default Kindle Key after 0.3 seconds
Found k4Mac kinf2018 file: /Users/dirklinnenbruegger/Library/Containers/com.amazon.Kindle/Data/Library/Application Support/Kindle/storage/.kinf2018
trying username b'dirklinnenbruegger' on file /Users/dirklinnenbruegger/Library/Containers/com.amazon.Kindle/Data/Library/Application Support/Kindle/storage/.kinf2018
trying IDString: b'27253a811823'
trying IDString: b'27253a811822'
trying IDString: b'27253a81182d'
trying IDString: b'931194f45ae5'
trying IDString: b'c59bfafc9990'
Decrypted key file using IDString 'c59bfafc9990' and UserName 'dirklinnenbruegger'
DeDRM v10.0.9: Found 1 new key
Decrypting KFX-ZIP ebook: c8vbpth0
Got DSN key from database key_0
Found 1 keys to try after 2.7 seconds
Traceback (most recent call last):
File "calibre_plugins.dedrm.init", line 931, in KindleMobiDecrypt
book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 203, in GetDecryptedBook
mb.processBook(totalpids)
File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 67, in processBook
self.decrypt_voucher(totalpids)
File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 88, in decrypt_voucher
raise Exception("The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher")
Exception: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 965, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,newkeys.items(),[],[],[],self.starttime)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 203, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 67, in processBook
    self.decrypt_voucher(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 88, in decrypt_voucher
    raise Exception("The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher")
Exception: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher
DeDRM v10.0.9: Ultimately failed to decrypt after 2.7 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
Running file type plugin DeDRM failed with traceback:
Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 931, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 203, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 67, in processBook
    self.decrypt_voucher(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 88, in decrypt_voucher
    raise Exception("The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher")
Exception: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre/customize/ui.py", line 214, in _run_filetype_plugins
  File "calibre_plugins.dedrm.__init__", line 1030, in run
    decrypted_ebook = self.KindleMobiDecrypt(path_to_ebook)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "calibre_plugins.dedrm.__init__", line 981, in KindleMobiDecrypt
    raise DeDRMError("{0} v{1}: Ultimately failed to decrypt after {2:.1f} seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md".format(PLUGIN_NAME, PLUGIN_VERSION,time.time()-self.starttime))
calibre_plugins.dedrm.DeDRMError: DeDRM v10.0.9: Ultimately failed to decrypt after 2.7 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
Conversion options changed from defaults:
  output_profile: 'generic_eink'
  cover: '/var/folders/q2/540ks_l50qg7pm7msw_dhpjr0000gn/C/calibre-2be_wpaf/6n023_h3.jpeg'
  read_metadata_from_opf: '/var/folders/q2/540ks_l50qg7pm7msw_dhpjr0000gn/C/calibre-2be_wpaf/06mdwne9.opf'
  verbose: 2
Resolved conversion options
calibre version: 8.9.0
{'add_alt_text_to_img': False,
 'allow_conversion_with_errors': False,
 'asciiize': False,
 'author_sort': None,
 'authors': None,
 'base_font_size': 0.0,
 'book_producer': None,
 'change_justification': 'original',
 'chapter': "//*[((name()='h1' or name()='h2') and re:test(., "
            "'\\s*((chapter|book|section|part)\\s+)|((prolog|prologue|epilogue)(\\s+|$))', "
            "'i')) or @class = 'chapter']",
 'chapter_mark': 'pagebreak',
 'comments': None,
 'cover': '/var/folders/q2/540ks_l50qg7pm7msw_dhpjr0000gn/C/calibre-2be_wpaf/6n023_h3.jpeg',
 'debug_pipeline': None,
 'dehyphenate': True,
 'delete_blank_paragraphs': True,
 'disable_font_rescaling': False,
 'dont_split_on_page_breaks': False,
 'duplicate_links_in_toc': False,
 'embed_all_fonts': False,
 'embed_font_family': None,
 'enable_heuristics': False,
 'epub_flatten': False,
 'epub_inline_toc': False,
 'epub_max_image_size': 'none',
 'epub_toc_at_end': False,
 'epub_version': '2',
 'expand_css': False,
 'extra_css': None,
 'extract_to': None,
 'filter_css': '',
 'fix_indents': True,
 'flow_size': 260,
 'font_size_mapping': None,
 'format_scene_breaks': True,
 'html_unwrap_factor': 0.4,
 'input_encoding': None,
 'input_profile': <calibre.customize.profiles.InputProfile object at 0x110366950>,
 'insert_blank_line': False,
 'insert_blank_line_size': 0.5,
 'insert_metadata': False,
 'isbn': None,
 'italicize_common_cases': True,
 'keep_ligatures': False,
 'language': None,
 'level1_toc': None,
 'level2_toc': None,
 'level3_toc': None,
 'line_height': 0.0,
 'linearize_tables': False,
 'margin_bottom': 5.0,
 'margin_left': 5.0,
 'margin_right': 5.0,
 'margin_top': 5.0,
 'markup_chapter_headings': True,
 'max_toc_links': 50,
 'minimum_line_height': 120.0,
 'no_chapters_in_toc': False,
 'no_default_epub_cover': False,
 'no_inline_navbars': False,
 'no_svg_cover': False,
 'output_profile': <calibre.customize.profiles.GenericEink object at 0x110557590>,
 'page_breaks_before': '/',
 'prefer_metadata_cover': False,
 'preserve_cover_aspect_ratio': False,
 'pretty_print': True,
 'pubdate': None,
 'publisher': None,
 'rating': None,
 'read_metadata_from_opf': '/var/folders/q2/540ks_l50qg7pm7msw_dhpjr0000gn/C/calibre-2be_wpaf/06mdwne9.opf',
 'remove_fake_margins': True,
 'remove_first_image': False,
 'remove_paragraph_spacing': False,
 'remove_paragraph_spacing_indent_size': 1.5,
 'renumber_headings': True,
 'replace_scene_breaks': '',
 'search_replace': '[]',
 'series': None,
 'series_index': None,
 'smarten_punctuation': False,
 'sr1_replace': None,
 'sr1_search': None,
 'sr2_replace': None,
 'sr2_search': None,
 'sr3_replace': None,
 'sr3_search': None,
 'start_reading_at': None,
 'subset_embedded_fonts': False,
 'tags': None,
 'timestamp': None,
 'title': None,
 'title_sort': None,
 'toc_filter': None,
 'toc_threshold': 6,
 'toc_title': None,
 'transform_css_rules': '[]',
 'transform_html_rules': '[]',
 'unsmarten_punctuation': False,
 'unwrap_lines': True,
 'use_auto_toc': False,
 'verbose': 2}
DeDRM v10.0.9: Trying to decrypt c8vbpth0.kfx-zip
Decrypting KFX-ZIP ebook: c8vbpth0
Found 1 keys to try after 0.0 seconds
DeDRM v10.0.9: Failed to decrypt with error: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher
DeDRM v10.0.9: Looking for new default Kindle Key after 0.0 seconds
Found k4Mac kinf2018 file: /Users/dirklinnenbruegger/Library/Containers/com.amazon.Kindle/Data/Library/Application Support/Kindle/storage/.kinf2018
trying username  b'dirklinnenbruegger'  on file  /Users/dirklinnenbruegger/Library/Containers/com.amazon.Kindle/Data/Library/Application Support/Kindle/storage/.kinf2018
trying IDString: b'27253a811823'
trying IDString: b'27253a811822'
trying IDString: b'27253a81182d'
trying IDString: b'931194f45ae5'
trying IDString: b'c59bfafc9990'
Decrypted key file using IDString 'c59bfafc9990' and UserName 'dirklinnenbruegger'
DeDRM v10.0.9: Found 1 new key
Decrypting KFX-ZIP ebook: c8vbpth0
Got DSN key from database key_0
Found 1 keys to try after 2.4 seconds
Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 931, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 203, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 67, in processBook
    self.decrypt_voucher(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 88, in decrypt_voucher
    raise Exception("The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher")
Exception: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 965, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,newkeys.items(),[],[],[],self.starttime)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 203, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 67, in processBook
    self.decrypt_voucher(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 88, in decrypt_voucher
    raise Exception("The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher")
Exception: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher
DeDRM v10.0.9: Ultimately failed to decrypt after 2.4 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
Running file type plugin DeDRM failed with traceback:
Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 931, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 203, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 67, in processBook
    self.decrypt_voucher(totalpids)
  File "/Users/dirklinnenbruegger/Library/Preferences/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 88, in decrypt_voucher
    raise Exception("The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher")
Exception: The .kfx-zip archive contains an encrypted DRMION file without a DRM voucher

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre/customize/ui.py", line 214, in _run_filetype_plugins
  File "calibre_plugins.dedrm.__init__", line 1030, in run
    decrypted_ebook = self.KindleMobiDecrypt(path_to_ebook)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "calibre_plugins.dedrm.__init__", line 981, in KindleMobiDecrypt
    raise DeDRMError("{0} v{1}: Ultimately failed to decrypt after {2:.1f} seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md".format(PLUGIN_NAME, PLUGIN_VERSION,time.time()-self.starttime))
calibre_plugins.dedrm.DeDRMError: DeDRM v10.0.9: Ultimately failed to decrypt after 2.4 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
InputFormatPlugin: KFX Input running
on /var/folders/q2/540ks_l50qg7pm7msw_dhpjr0000gn/C/calibre-2be_wpaf/c8vbpth0.kfx-zip
Software versions: KFX Input 2.26.2, calibre 8.9, macOS-15.6.1-arm64-arm-64bit
KFX Input plugin help is available at https://www.mobileread.com/forums/showthread.php?t=291290
Converting /var/folders/q2/540ks_l50qg7pm7msw_dhpjr0000gn/C/calibre-2be_wpaf/c8vbpth0.kfx-zip
Processing container: Radikal führen_B09XBNWYTW.kfx
Traceback (most recent call last):
  File "calibre_plugins.kfx_input.__init__", line 96, in convert
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 213, in decode_book
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 331, in get_container
calibre_plugins.kfx_input.kfxlib.utilities.KFXDRMError: Book container Radikal führen_B09XBNWYTW.kfx has DRM and cannot be converted

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "runpy.py", line 198, in _run_module_as_main
  File "runpy.py", line 88, in _run_code
  File "site.py", line 42, in <module>
  File "site.py", line 38, in main
  File "calibre/utils/ipc/worker.py", line 213, in main
  File "calibre/gui2/convert/gui_conversion.py", line 39, in gui_convert_override
  File "calibre/gui2/convert/gui_conversion.py", line 26, in gui_convert
  File "calibre/ebooks/conversion/plumber.py", line 1089, in run
  File "calibre/customize/conversion.py", line 242, in __call__
  File "calibre_plugins.kfx_input.__init__", line 116, in convert
calibre.ebooks.DRMError: This book has DRM!

[30.31] Shutdown starting...
[32.57] Shutdown complete, quitting...

[dlinnenbruegger-ops]

Here we go

[ElleKayEm]

All I can tell from this conversion attempt is that the DRM voucher isn't in the KFX-ZIP. Let's see a debug log from just adding the file to calibre. When adding the book are you leaving the kfx in its original folder structure?

[dlinnenbruegger-ops]

I finally got it, copied all master data as well and finally it worked. Many thanks to you

[siberian1967]

@dlinnenbruegger-ops Can you detail what you did? I am getting the same errors when I import the KFX file from its original location as downloaded by kindle 2.7 for windows. Fresh install of everything today.

[ElleKayEm]

Right there at the top of the list on the forks page. Here's a direct link to the latest release:
https://github.com/Satsuoni/DeDRM_tools/releases/tag/v10.0.12s1

[siberian1967]

@siberian1967 noDRM's DeDRM doesn't work with the latest Kindle for PC. If you don't have an E-ink Kindle and you're trying to DeDRM a book published after April 22, 2025, try Satsuoni's fork DeDRM 10.0.12.

The book is pretty old, from 2005 or so, although I just downloaded it today so maybe its using the newer encryption. The fork did not work so I think I am SOL.

[ElleKayEm]

Then you can download it with an older version of Kindle for PC and that should work.

[siberian1967]

Then you can download it with an older version of Kindle for PC and that should work.

I think they have disabled the older versions but I'll keep probing. tx! Until that I am having to use Shotomatic to autocapture the entire kindle cloud book and PDFGear to OCR. PITA.

[ElleKayEm]

They've just disabled downloads on older Kindle for PC for books published after April 22, 2025. See method 2a here: https://www.mobileread.com/forums/showthread.php?t=361503

Satsuoni's DeDRM works on the latest Kindle for PC, but you do have to extract new keys using the seperate key extractor every time you download new books. So that's a bit of a PITA too.

[rjacobs07]

This may or may not have been the issue for you, but I was having the same problem. My books were importing into Calibri as KFX-ZIP files. Previously, things had worked fine with just KFX files, but now I received the dreaded error message you got.

After some random troubleshooting, I realized that if I changed the name of the book file in File Explorer (under documents, my kindle content, etc.) than the file type would change to KFX-ZIP instead of just a normal KFX file. When I redownloaded it in Kindle, left the file name alone, and uploaded it into Calibri, it came as a normal KFX file. I could then follow the standard process to convert it, without any issues.

Hope that helps someone!

[ElleKayEm]

Yes, messing with the original file names or folder structure prevents KFX Input from gathering the other needed files.