[Synamon]

This isn't actually the correct subforum, it's for recipes used with the Fetch News feature of calibre, which probably explains why you're not getting responses.

Downoads to each Kindle device (including the Kindle for PC program) have their own DRM locking them to that device. You cannot read DRM'd books on a Kindle if they were downloaded from Amazon for a different Kindle or for the Kindle for PC program. If you've downloaded books to the Kindle for PC program in order to get the books on your computer so you can put them in calibre, they are not properly coded to use on your Kindle.

Instead, for books you've already purchased, use the the 'Download and transfer via USB option' in the Actions button of your Kindle Library from your Manage Your Kindle page and select your Kindle as the device. When you buy new books, select the 'Transfer to Computer' option and choose the Kindle you want the DRM to match. This will download books that are compatible with reading on your Kindle to your computer and you can add them to calibre and edit the metadata and transfer them to your Kindle from there.

Another workaround involves stripping the DRM, which can't be described here, but information can be found by googling Apprentice Alf.