how to fix error (2009)
iphone'iphone'could not be restored .an unknown erroe (2009)
iPhone 3G, iOS 3.1.3
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Error 2000-2009 (2001, 2002, 2005, 2006, 2009, and so on)
If you experience this issue on a Mac, disconnect third-party devices, hubs, spare cables, displays, reset the SMC, and then try to restore. If you're using a Windows computer, remove all USB devices and spare cables other than your keyboard, mouse, and the device, restart the computer, and try to restore. If that doesn't resolve the issue, try the USB issue-resolution steps listed for Error 1604 above. If the issue persists, it may be related to conflicting security software. If the errors persist on another computer and known-good USB cable, the device may need service.
iTunes: Specific update-and-restore error messages and advanced troubleshooting