For your iPhone to sync with iTunes, it must trust the computer first. In other words, it’s only after trusting a computer that your iPhone will allow data transfer (photos, music, contacts, videos, etc.) to occur between itself and that particular computer. If your iPhone distrusts a computer, it treats it as a mere charging device whenever you connect them using a USB cable. This article explains the procedures of how to get iPhone to trust computer.
When you connect your unlocked iPhone to a computer, a notification box with the question “Trust This Computer?” should pop up on your iPhone screen. That confirms to you that your iPhone doesn’t trust nor distrust that computer. In that case, you can proceed to trust/distrust it. If the notification doesn’t appear, then there are two possibilities:
If you select Don’t Trust as explained in the last point above, the trust notification will never pop up on your iPhone until the time you will change its privacy settings. If, for whatever reasons, you have changed your mind and you now want to trust the computer, proceed as follows.
Maybe you wanted to distrust a computer but you mistakenly trusted it, or maybe you used to trust a computer but you now doubt its “trustworthiness”. This is how to make amends:
Always remember that the trust notification on your iPhone is a security precaution. You must, therefore, be very cautious when trusting any computer.
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