Having trouble transferring books from computer to Kindle.

You need to log in the same kindle account and the purchased books will be synced automatically. If this doesn't work, you can convert the kindle books to epub file and transfer to ipad. You need to connect your Kindle device to computer and then convert the books in Kindle. After that, you can transfer the books to ipad with iTunes or iTransfer. For more details, check: A Simple Guide to Help You Read Kindle Books on iPad

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For DRM free eBooks, you can easily transfer them to other Kindle devices with USB cable freely. You just need to simply plug your Kindle to computer with the USB cable, then there will be a removable disk, open the disk and find the books you want to transfer to other Kindles, then copy them out to your local drive. Read more...

For any help or support just visit us: Kindle Fire Support

Connect your previous Kindle to computer via USB, and you will find a new hard drive in "My Computer". Open the drive, use windows search function to find your files, next copy them into your computer. ... If your books are not bought from amazon, you can sync your kindle booksfrom kindle to another one easily.

How can I transfer books from one Kindle to another Kindle? - Quora

https://www.quora.com/How-can-I-transfer-books-from-one-Kindle-to-another-Kindle Can transfer my books from one kindle to another Google Search

Two methods.
First: A computer is required. Connect the old Kindle to the computer it should show up as a new drive. Open that drive and find the books. Transfer them to the computer. Plug in new Kindle and do the same only transfer the transferred books from the computer onto the new Kindle.
Two: If you purchased the books from sources like Amazon, your books are saved on their cloud. Simply connect your new device and download all your books again.

You are able to move the books to computer, and then sync ebooks to iPad with iTunes. When the Kindle users connect their Kindle tablets to computer with the USB cable, their computers will recognize their Kindle tablets as external hard drives. Then the users can copy and paste the ebooks from Kindle to computer easily. After that, the users are able to sync the books from computer to iPad with iTunes.

This is easy to be done. But when users begin to sync their iPad with iTunes, they may come up with the sync problems of iTunes. The problem may come up when users sync ebooks from iTunes to iPad. During the sync, iTunes will erase all the non-purchased items in your iPad mini. If you are new to iOS devices, you will probably lose files during the sync with iTunes, so you'd better close the auto sync and manually sync the ebooks to your iPad mini with iTunes. The following tutorial will be helpful if you aren't sure about how to accomplish the task:

1. Start iTunes and go to "Edit > Preference > Devices", and check "Prevent iPods, iPhones and iPads from syncing automatically".
2. Plug iPad into computer via USB cable, and the software will recognize your iPad and display the iPad icon at the upper right corner.
3. Click the iPad icon and choose "Books" in the summary panel. Choose the books you want to sync to iPad in the list below, and click "Apply" to start.

How to Transfer Ebooks from Kindle to iPad mini

How to transfer kindle books from computer to kindle via usb

You can easily load all of your books onto your new Kindle. Amazon retains a record of all your book purchases in an archive. When you register your new Kindle (and turn on wireless) it 'phones home' to Amazon and Amazon places an entry on your main menu entitled Archive. Just click on that entry and all of your past book purchases will appear and will automatically be downloaded to the Kindle when you click on them.

However, if your old Kindle contained any books, pictures, or documents that you did NOT purchase from Amazon, those items will not appear in the Amazon archive. You will have to download those items to your new Kindle the same way you installed them on the old Kindle. If the only location of those un-archived documents is the old Kindle, then this will become a two step process because you cannot copy from one Kindle directly to another. Instead you must copy the documents off the old Kindle onto a computer using the USB cable, and then copy the books from the computer onto the new Kindle by way of the USB cable or by email using an authorized email account. (To authorize an email account for sending books to your Kindle, please visit Amazon's "manage my devices" section. If the new Kindle is not registered, or if it is blacklisted, then you cannot use the email method to transfer the books. The only way to install books on an unregistered Kindle is directly via USB cable.)

To transfer books from CD to your Kindle you will need to use a computer and connect your Kindle to that computer by USB then copy the books from the CD to the Kindle folder that you can find via Windows Explorer.

See the help information for Transferring files via USB on the Kindle Support web site for further details on doing this.