Failed to restore iphone - How to continue?

Hi,

When starting an app on the iPhone 4S, quick regualrly, the apps stops immediately (back to home screen) or even the Apple logo appears.

I already resetted to Factory settings several times to solve the issue, but this remains.

Finally, I tried to restore the Apple iOS (6.1.3) via iTunes. Initially, everything started fine (downloading, unpacking), but when the image is transferred to the iPhone, it suddenly stops (at the iPhone display, the Apple logo and a progress bar are visible, approx. 5%): " Unable to restore image"

The iPhone reboots and indicates that the iPhone must be connected to iTunes. Then it starts all over again. iTunes indicates that it has detected an 4S in recovery mode and proposes to recover. As the downloaded firmware is still in cache, it starts with unpacking the downloaded firmware file and when transferring to the iPhone, it stops again. I already repeated this multiple times, sometimes it stops with different error messages (values).

The error message when stopping varies from -1, 9, 14. Based on the details explanation that can be retrieved, Apple recommends a number of actions:

- Install latest version of iTunes (which is already the case)

- Change cable

- Change usb port

- Disable Virus protection

- Change computer

- ...

I tried all (computers with WinXp, W7, W8), 3-4 cables, all USB ports, ... nothing helps.

The iPhone simply won't start (only the connect to iTunes logo occurs).

BTW: the iPhone has NEVER been jailbreaked, one original images (6.1.0 and 6.1.3) have been installed.

Does anyone have an idea how to solve this?

Ilona