I'm trying to open a purchased book and keep getting the message that failed to load book because requested source is missing I go into store and it shows it downloaded. What am I doing wrong?
Try deleting the book from the bookshelf in the iBooks app (Edit button top right) and then redownload it via the Purchased tab in the ibookstore and see if you can open that copy.
If that doesn't work, you may want to try deleting and redownloading the iBooks app.
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