Either use the 'Connect to iTunes' method to transfer content to your iPad, or create a ticket and attach a debug log from starting calibre until the problem occurs. You can find instructions on creating a ticket in the 'If you have problems' section of the
Calibre +iDevices: Start here sticky.
A small number of users are unable to reliably transfer content using the direct connection method, as I mentioned in the first post in this thread. You might also look at using calibre's content server to add books to your iPad.
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