this is from tech arena.This is also for ipods
Error 9 Unknown
The error 9 means that the iphone was unplugged when handling, it is advised to change usb cable, usb port. (Do not use the Hub)
If problem remains unsolved despite your attempts to Restore in Recovery Mode and DFU, contact service Apple.
This error occurs when the device has been inadvertently disconnected from the USB bus and the communication stopped. This can occur if the device is disconnected manually during the restoration process. You can solve it by making a USB troubleshooting isolation, using a different USB cable dock connector, trying other USB ports, performing the restore on another computer or removing conflicts caused by third-party security software.