Re-import it into caliber, or delete it from caliber and then open it in Caleb the first time. Then the DRM will be removed. How to remove DRM from e-Book on Kindle, Kindle Voyage, Nook, Kobe, Sony Reader, Pocket, Sony iPod & other Smart Books Sep 11, 2023 — Here's the guide I used to remove DRM on my Kindle. If you need some help, feel free to contact me. All you have to do is download the Kindle DRM Removal Guide — Step By Step 1 — Download My Book Remove DRM Step 2 — Start Caliber, click the Preferences… button, and in the drop-downs' menu, select General → Text, and then click the Read & Apply tab. Note that the Kindle's serial number doesn't exactly match the serial number stored in caliber. Step 3 — Click the ‹Read & Apply… button in the General tab, and then navigate to Step 4 above. Note: You may also end up here if the .pub for the book contains no DRM. Just click the ‹Read & Apply… button in the General tab and navigate to Step 5. Step 4 — Scroll down to ‹Device & serial number and replace the entire string with the serial number from caliber's device, if it is different. Then click the ‹Read & Apply… button in the General tab, and then navigate to Step 6 above. Step 5 — Click the ‹Read & Apply… button. Step 6 — Scroll down to ‹Device & serial number and replace the entire string with the serial number from caliber's device, if it is different. Then click the ‹Read & Apply… button. Step 7 — Click the ‹Read & Apply… button. Step 8 — The whole process may take a while to complete. After the DRM has been removed, you can re-download the book at your leisure as long as you still have caliber installed. You can also start Caliber and re-apply the device, if required. How to download and install caliber and a few free plugins on Ubuntu 15.