How to troubleshoot iBooks problemsHaving a problem with iBooks? Here's how to fix it.
If you're having issues downloading your ebooks or audiobooks in iBooks, getting configuration errors, or other problems, here are a few fixes you can try.
Can't download? Check your cellular data
Are you getting an error when trying to view the iBooks Store or redownloading an iCloud-stored book in your library? You might have cellular data disabled on your iPhone or iPad. You can check by visiting the Settings app.
Launch Settings from your Home screen.
Scroll down and tap iBooks.
Flip the switch next to Cellular Data, under Allow iBooks to Access.
Can't read? Try redownloading
If your book displays strange errors or doesn't look quite right, it may have gotten garbled on download. Rather than suffer through a badly-formatted book, you may want to try deleting the book and redownloading it. Warning: You'll lose any annotations and highlights when you delete the book.
Tap on the My Books tab. It's in the bottom left corner ...
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How to troubleshoot iBooks problems