What do I do if my Iphone does not start up anymore?
Here basic troubleshooting:
1 Try turning Iphone off, then back on. Turn it off by holding down the Sleep/Wakebutton until you see the red slider on display, then slide the finger across theslider. To turn iPhone back on, hold down theSleep/Wake button until the you see Apple logo on display.
2 Try pressing and holding the Home button for about ten seconds. This will close a frozen application or a stuck process. After this restart the iPhone following thesteps on point one.
3 If the above did not work, try doing a reset. Hold down the Sleep/Wake button and the Homebutton at the same time for about 10 seconds. You may see ared "power off" slider appearing on screen, then you see the display going black. Donot release Sleep/Wake and Home buttons until you see the Apple logo appearing on display. See picture below:
4 Reset all settings: Tap Settings>General>Reset> Reset All Settings. This will reset all settings to factory default. Data and media files will not be affected.
5 If that does not fix the problem, then try deleting all content and settings.
Tap Settings>General>Reset>Erase All Contents and Settings
This will delete all media and data. All settings will also be reset to default value.
6 Try restoring iPhone using the latest version of iTunes.
Connect iPhone to the computer using the data cable. When you see the IPhone in the Source list, click on Restore in the Summary tab.
If that did not work, repeat steps from 4 to 6 once more. If Iphone is still frozen, unplug it from pc, and try restarting the Iphone. Also reinstall Itunes and connect Iphone to pc again.
Ifrepeating the steps 4 to 6 did not fix your problem , then the Iphone isfaulty. In that case take it to a local Apple repair shop, or call Apple servicephone number listed on the user guide to arrange repair.
If the Iphone is faulty, sometimes reinstalling Firmware can fix it, but that, that is a risky procedure that will invalidate your warranty and damage the IPhone beyond repair. Better calling Apple before bricking the Iphone.
For this reason I will only post links on the argument.
On firmware update see:How To Install IPhone FirmwareIPhone Firmware Download Links