The easiest thing to try is restoring the iPhone on anohter computer.
See this Apple doc for other more specific ideas -> Resolve specific iTunes update and restore errors
Check for hardware issues
Related errors: 1, 3, 10-47, 1002, 1011, 1012, 1014, 1000-1020, 1669.
Try to restore your iOS device two more times while connected with a cable, computer, and network you know are good. Also, confirm your security software and settings are allowing communication between your device and update servers. If you still see the error message when you update or restore, contact Apple support.