DRM not working, showing key not found

[10la5-Veygarn]

I've been trying to upload 1 of my books to calibre for a long time. When I tried using Command prompt, it gives this as error logs -
C:\Users\ashis\B000FC1PPM_EBOK.azw not found
Gather KFX-ZIP (from KFX Input) 2.13.0: Importing C:\Users\ashis\Documents\Books\KKindle\B000FC1PPM_EBOK\B000FC1PPM_EBOK.azw
Gather KFX-ZIP (from KFX Input): Gathered 4 file(s) as C:\Users\ashis\AppData\Local\Temp\calibre_44tsc7qg\y7xie5c8.kfx-zip
DeDRM v7.2.1: Trying to decrypt y7xie5c8.kfx-zip
Using Library AlfCrypto DLL/DYLIB/SO
Using Library AlfCrypto DLL/DYLIB/SO
Decrypting KFX-ZIP ebook: y7xie5c8
Found 0 keys to try after 0.1 seconds
Decrypting KFX DRM voucher: amzn1.drm-voucher.v1.6ff325b3-b2ec-4eae-a8ab-7bbd7f48ddb0.voucher
Traceback (most recent call last):
File "calibre_plugins.dedrm.kfxdedrm", line 83, in decrypt_voucher
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 879, in decryptvoucher
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 758, in pkcs7unpad
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 98, in _assert
Exception: Incorrect padding - Wrong key
DeDRM v7.2.1: Failed to decrypt with error: Failed to decrypt KFX DRM voucher with any key
DeDRM v7.2.1: Looking for new default Kindle Key after 0.1 seconds
searching for kinfoFiles in C:\Users\ashis\AppData\Local
Found K4PC 1.25+ kinf2018 file: C:\Users\ashis\AppData\Local\Amazon\Kindle\storage.kinf2018
Decrypted key file using IDString '1657514253' and UserName 'Agastya'
DeDRM v7.2.1: Found 1 new key
Decrypting KFX-ZIP ebook: y7xie5c8
Got DSN key from database default_key_1
Found 1 keys to try after 4.4 seconds
Decrypting KFX DRM voucher: amzn1.drm-voucher.v1.6ff325b3-b2ec-4eae-a8ab-7bbd7f48ddb0.voucher
Traceback (most recent call last):
File "calibre_plugins.dedrm.init", line 540, in KindleMobiDecrypt
File "calibre_plugins.dedrm.k4mobidedrm", line 238, in GetDecryptedBook
File "calibre_plugins.dedrm.kfxdedrm", line 45, in processBook
File "calibre_plugins.dedrm.kfxdedrm", line 89, in decrypt_voucher
Exception: Failed to decrypt KFX DRM voucher with any key

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "calibre_plugins.dedrm.kfxdedrm", line 83, in decrypt_voucher
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 879, in decryptvoucher
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 758, in pkcs7unpad
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 98, in _assert
Exception: Incorrect padding - Wrong key
Traceback (most recent call last):
File "calibre_plugins.dedrm.init", line 540, in KindleMobiDecrypt
File "calibre_plugins.dedrm.k4mobidedrm", line 238, in GetDecryptedBook
File "calibre_plugins.dedrm.kfxdedrm", line 45, in processBook
File "calibre_plugins.dedrm.kfxdedrm", line 89, in decrypt_voucher
Exception: Failed to decrypt KFX DRM voucher with any key

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "calibre_plugins.dedrm.kfxdedrm", line 83, in decrypt_voucher
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 879, in decryptvoucher
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 758, in pkcs7unpad
File "C:\Users\ashis\AppData\Roaming\calibre\plugins\DeDRM.zip\ion.py", line 98, in _assert
Exception: Incorrect padding - Wrong key
DeDRM v7.2.1: Ultimately failed to decrypt after 4.4 seconds. Read the FAQs at Harper's repository: https://github.com/apprenticeharper/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 540, in KindleMobiDecrypt
File "calibre_plugins.dedrm.k4mobidedrm", line 238, in GetDecryptedBook
File "calibre_plugins.dedrm.kfxdedrm", line 45, in processBook
File "calibre_plugins.dedrm.kfxdedrm", line 89, in decrypt_voucher
Exception: Failed to decrypt KFX DRM voucher with any key

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "calibre\customize\ui.py", line 199, in _run_filetype_plugins
File "calibre_plugins.dedrm.init", line 633, in run
File "calibre_plugins.dedrm.init", line 583, in KindleMobiDecrypt
calibre_plugins.dedrm.DeDRMError: DeDRM v7.2.1: Ultimately failed to decrypt after 4.4 seconds. Read the FAQs at Harper's repository: https://github.com/apprenticeharper/DeDRM_tools/blob/master/FAQs.md
Package KFX (from KFX Input) 2.13.0: Packaging C:\Users\ashis\AppData\Local\Temp\calibre_44tsc7qg\y7xie5c8.kfx-zip
Processing container: B000FC1PPM_EBOK.azw
Running file type plugin Package KFX (from KFX Input) failed with traceback:
Traceback (most recent call last):
File "calibre\customize\ui.py", line 199, in _run_filetype_plugins
File "calibre_plugins.kfx_input.package_filetype", line 23, in run
File "calibre_plugins.kfx_input.package_filetype", line 34, in package_kfx
File "calibre_plugins.kfx_input.kfxlib.yj_book", line 79, in convert_to_single_kfx
File "calibre_plugins.kfx_input.kfxlib.yj_book", line 212, in decode_book
File "calibre_plugins.kfx_input.kfxlib.yj_book", line 321, in get_container
calibre_plugins.kfx_input.kfxlib.utilities.KFXDRMError: Book container B000FC1PPM_EBOK.azw has DRM and cannot be converted
KFX metadata reader (from KFX Input) activated for C:\Users\ashis\AppData\Local\Temp\calibre_44tsc7qg\5jhpqbsyadd-multiple\1\B000FC1PPM_EBOK.kfx-zip
Added book ids: 1, 2

Closest I could figure out, Calibre can't automatically get the key for Kindle for PC. I'm using version 2.2.0 (70623) with Calibre version 7.12, the latest version of DeDRM from this repository (not the auto-release, downloaded yesterday), and the KFX Input plugin from the forum (also downloaded yesterday).

Edit: I tried to use the 'kindlekeys.py' program sepaately, and it gave me this error:
Traceback (most recent call last):
File "D:\AGASTYA\kindlekey.py", line 1798, in gui_main
keys = kindlekeys()
^^^^^^^^^^^^
File "D:\AGASTYA\kindlekey.py", line 1686, in kindlekeys
key = getDBfromFile(file)
^^^^^^^^^^^^^^^^^^^
File "D:\AGASTYA\kindlekey.py", line 1136, in getDBfromFile
from Crypto.Cipher import AES
ModuleNotFoundError: No module named 'Crypto'

[ElleKayEm]

Log shows DeDRM 7.2.1.

[10la5-Veygarn]

Solved using ChatGPT. Apparently, you need Microsoft C++ language pack (V 14 and above) to run the pycrypto module, which retrieves the key for DeDRM.