The first thing to do when your iPhone won’t turn on is to make sure it’s on. While that might sound like a no brainer, it can be surprising to find out your iPhone was actually turned off. You can make sure that it’s on though by holding the Hold button down for a few seconds. Then, the iPhone will turn on or you will see the slider that allows you to turn it off. If the slider does appear, go ahead and turn your iPhone off and them back on to see if that will correct the problem.
If your iPhone still won’t start after trying to start or re-start it, then press down on the Hold and Home buttons at the same time for at least ten seconds or more to see if the iPhone will start to boot back up. If this doesn’t work, place your iPhone on its charger and allow it to charge for twenty minutes or so. Then see if it will turn on. While you are doing this, check to make sure your iPhone is charging because it could be that there is a problem with your charger or cable that is not allowing the iPhone to get enough power to turn on.
If you are sure your charger and cable are working to properly charge your iPhone and it still won’t start, then you may need to return it to the factory settings. While this will erase all your device’s data and settings, you should be able to restore it from an iCloud or iTunes backup after you have been able to get the iPhone to turn back on. To restore to factory settings when your iPhone won’t turn on, connect it to the dock computer and not a computer. While it is connected, hold down the HOME button then plug the other end into your computer. This will prompt iTunes to open on your computer and this will put your iPhone into recovery mode so you can restore it to factory settings.
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