Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
How To Install iOS 7 On Your iPhone, iPad and iPod Touch
Apple is set to release iOS 7 to the public later today around 6PM GMT so we thought it is about time we published a guide on how you can update to iOS 7 on your iPhone, iPad and iPod touch.
The first thing you want to do is make sure your device is compatible with iOS 7. All compatible devices can be seen in the image below.
Anything can happen when updating to a new operating system so we encourage you to back up everything on your device before hand and also in as many ways as possible, starting of with iCloud. Backing up your device to iCloud is fairly straight forward, on your device go to Settings > iCloud > Backup & Storage, and click Back Up Now. Everything should go to plan as long as you have got enough space available.
Backing up to iTunes is simple and means you have a local copy of your backup, to do this connect your device to you computer, sync with iTunes and once that is done you can click on your connected device and click Back Up Now.
Download / Install
There is two ways you can update your device, one being through iTunes and the other by using the OTA ( Over the air) software update that Apple introduced in iOS
Starting of with OTA, it is advised that you plug your device in to a power source and also have your phone connected to WiFi as downloading iOS 7 could push a couple of you over your data allowance. Once you have made sure of all the above go to the Settings app on your device and then General > Software Update. If iOS 7 has been pushed yet you will see it on this screen but if not then it will appear soon as you can imagine you are one of thousands trying to access this file to download. Once iOS 7 appears as a software update press download, this will take a few minutes especially on launch day. The download will work in the background meaning you can still use you device as normal, once downloaded you will receive a notification telling you that you can now install iOS 7 and about 20 seconds after clicking that your will be using iOS 7.
Regarding updating to iOS 7 on iTunes the first thing to make sure is that you are using the latest version of iTunes. After you have made sure you are running the latest version of iTunes plug your device in via the USB cable and iTunes will prompt you with the device summary page, then click software update and if iOS 7 is available then it will ask you if you want to download it and install. Once you have done that iTunes will take over, like we said earlier iOS 7 may take a while to download on launch day just due to the fact that so many people are trying to access Apple’s servers.
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