If a security warning appears, click , then Restart Calibre . 3. Adding Your Kindle Serial Number
Find under "File type plugins," click it, and select Customize plugin . If a security warning appears, click , then Restart Calibre
: On the Amazon website , go to Manage Your Content and Devices . Next to a book, select More actions > Download & transfer via USB . Choose your Kindle device and download the file. Drag this file into Calibre. If a security warning appears