The Lulu Print API is separate from the Lulu platform in terms of file sharing. Therefore, Lulu.com books cannot be used for print jobs. Book files for API print jobs must be hosted remotely on a server, Google Drive, Dropbox, or an online shared folder. While it is not possible to access Lulu account book files directly through the Lulu API, you can download the print-ready files from your Lulu account, upload these files to your preferred shared online storage location, then use them for print jobs.Note: It is important to ensure that the folder storing the book files is not blocked by security or password protected, and is open to sharing files. If the folder is not accessible the print job request will fail.