My I-phone 4 has upgraded to IOS-7 and now it will only be "ON" if plugged into a wall outlet. It shows a full battery, but as soon as I disconnect the cable, the phone cuts off. This never happened before and started as soon as the upgrade completed. I tried to connect to my computer to see if I-tunes would recognize it, but the phone will not power on while plugged into the computer.
Well the first part of the issue is the phone always stays on while charging via power outlet. Mine has never shut off during or after a charge. Even if the iphone is off when you plug into the power it powers on and stays on.
Second part of your concern. Well download the iTunes 11.1 first. Turn your computer on and off, since it needs to restart.
After bring up the iTunes program, plug the usb cable into the device and into your computer, top corner of iTunes will show your device. Click it and do what you want.
The new iTunes and the new iOS 7 can now be synchronize via bluetooth so that may also be the way to go.
This is very strange! You need your phone to stay on when unplugged. I had similar issues when updating software on other devices and a factory reset always clear any system error encountered during the software update. Give it a try! http://bit.ly/LdGqLl
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