iPhone Error Number 9
Error 9: This error occurs when the device unexpectedly drops off the USB bus and communication stops. This can occur if the device is manually disconnected during the restore process. This issue can be resolved by performing USB isolation troubleshooting, using a different USB dock-connector cable, trying another USB port, restoring on another computer, or by eliminating conflicts from third-party security software.
There are reports that the problem was solved by:
1. Disconnect the USB cable from the iPhone
2. Disconnect the USB cable from the Computer
3. Connect the USB cable to a different USB port
4. Connect the USB cable to your iPhone
5. In iTunes, try the restore process again