(1) Quit and restart iTunes
(2) Try to connect to a different USB port on the computer
(3) Reboot the iPhone, iPad or iPod and press the button of Power and Home simultaneously until the icon of Apple appear
(4) Reboot the computer
(5) Use a different syncing cable
If the iTunes still can’t recognize the iPhone/iPad, probably, the problem is with the iTunes itself. You should delete it and its affiliate software, and reinstall. Here, take Window 7 as an example. Firstly, enter the control panel and follow the following steps to remove the iTunes in order.
Remove iTunes>QuickTime>Apple Software Update>Apple Mobile Device Support>Bonjour>Apple Application Support
Then reinstall the iTunes with the latest version from Apple’s official web:
If you have done all the solutions but the iPhone/iPad still can't be detected by iTunes, connect your iPad/iPhone to another computer. If the iTunes can still not recognize them, there could be a problem with some hardware of the device of iPhone/iPad, and you’ll probably want to call Apple to sort it out. If it works, the problem is with your original computer.
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