Version 6.6.1 of the tools is now available. Please update to the latest version if you are having issues.
DeDRM_tools_6.6.1.zip can be downloaded from
First release using the new directory structure and release script. Hopefully fixes the problem with KFX and the stand-alone tools.
To leave a comment, see the previous post: DRM Removal Tools for eBooks.
Thanks to work by several people, the tools can now decrypt KFX format ebooks from Amazon.
If using the calibre plugin, install the KFX Input Plugin to automatically locate all of the files that make up a KFX format book and gather them into a KFX-ZIP. After the DeDRM plugin removes the DRM, then the KFX Input Plugin will package it into a single KFX file.
If using one of the stand-alone apps, create a KFX-ZIP file by creating a ZIP archive of all of the files in a book subfolder within the main Kindle for PC/Mac content folder and then changing the file extension from “.zip” to “.kfx-zip”.