amazon has new ebook format since Kindle for Pc 1.19, new format call KFX format cause problems, we need to downgrade kindle for pc to old v1.17 or v1.24, kindle for Mac to v1.17, download ebook file in old version,
The good news is, Project Gutenberg and many other ebook resources offer downloads in a Kindle compatible format, usually Mobi. Some independent ebook sellers, such as Fictionwise, also sell. EPUB to Kindle Converter is a tool for the conversion of files from Epub to kindle with a simple click of the button. These tools are found as downloadable files for both Windows and Mac. At the same time, there is an online version, so, either way, you can be sure of getting your files sorted.