I got a new macbook and I can't sync the music from my iPhone to iTunes.. How do i do that?
The iphone is not a storage/backup device.
The sync is one way - computer iphone. The only exception is itunes purchases: File>Devices>Transfer Purchases
Copy everything from your old computer, or your backup copy of your old comptuer, to your new one.
Migrate your iTunes library form the old computer to the new one: http://support.apple.com/kb/HT4527
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