error 4005 on iphone 4S during ios 8 update

Check your USB connections

Related errors: 13, 14, 1600, 1601, 1602, 1603, 1604, 1611, 1643-1650, 2000, 2001, 2002, 2005, 2006, 2009, 4005, 4013, 4014, or “invalid response."

If the USB connection between your device and computer is interrupted, you may be unable to update or restore.

To narrow down the issue, you can also change up your hardware:

• Use the USB cable that came with your device, or a different Apple USB cable.
• Plug your cable into a different USB port directly on your computer. Don't plug it into your keyboard.
• Try a different computer.
• If necessary, resolve any further issues with the USB connection, then with your security software.

If you're still seeing the error message, check for hardware issues by following the next section.

Check for hardware issues

Related errors: 1, 3, 10, 11, 12, 13, 14, 16, 20, 21, 23, 26, 27, 28, 29, 34, 35, 36, 37, 40, 1000, 1002, 1004, 1011, 1012, 1014, 1667, or 1669.These errors mean that your device or computer may have a hardware issue that's preventing the update or restore from completing.

1. Check that your security software and settings aren't preventing your device from communicating with the Apple update server.
2. Then try to restore your iOS device two more times while connected with a cable, computer, and network you know are good.
3. Confirm that your security software and settings are allowing communication between your device and update servers.
4. If you still see the error message when you update or restore, contact Apple support.