IOS 6.1.4 was released by Apple for iPhone 5 a couple of days ago, but no change to baseband 3.04.25, so it is still possible to unlock it.
Here are common iTunes error when trying to restore your iPhone:
Error -1 Error occurs when one uses the “last ditch” method for preventing baseband updates on the iPhone 4. The baseband does not get updated using this method. Use TinyUmbrella to kick it out of recovery mode.
Not enter the downgrading mode, change USB port (the back one of chassis is better) and restart computer.
Updating to the latest version of iTunes and then restoring should resolve this issue
Error 20 Reportedly happens during failed downgrade attempts (iOS 2.0 to 1.1.1, 5 beta to 4.3.3).
Some have seen success afterwards by doing the downgrade from DFU mode instead of the normal Recovery mode.
Error 31 Main Article: DFU Loop
Error 34 Hard disk is run out of space when trying to download. Clear space and then continue downloading.
Error 1002 Error when restoring.
Error 1004 This is caused by a failure to match the Baseband Nonce currently in memory to the nonce returned in the Baseband Firmware SHSH blob. This happens if you edited the hosts file (Saurik’s Server) or you are using TinyUmbrella. Use TinyUmbrella and “Kick Device Out Of Recovery” to boot. 1
Error 1011 This is caused by recovery mode being in userland (1.1.1 firmware). The file iTunesMobileDevice.dll is damaged or updated.
Error 1015 This error is common when downgrading iPhones and 3G-enabled iPads. The problem occurs when the device’s baseband has a higher version number than the baseband in the firmware you restored to. Just set auto-boot true in iRecovery or use iREB/TinyUmbrella/RecBoot.1 In case this is not working use Pwnage Tool to create a custom firmware WITHOUT the iPad baseband, put your device in pwned DFU mode and restore via iTunes.
Error 1394 When Spirit2Pwn flashes parts of the boot chain on iOS 4, the device may crash into DFU Mode.
Error 1413 Restart computer; change USB port; reinstall system. See also Apple’s Knowledge Base article number TS1927.
Error 1415 Restart computer; change USB port; reinstall system.
Error 1417 Restart computer; change USB port; reinstall system.
Error 1418 Restart computer; change USB port; reinstall system.
Error 1428 Restart computer; change USB port; reinstall system. (downgrade from www.iphonebus.com)
Error 1050 Bad response from gs.apple.com OR need iREB for preparing the device for restoring to custom IPSW
Error 1600 - Custom firmware can’t be restored on a device with DFU Mode. The software of the iPhone isn’t patched. Using iREB, sn0wbreeze, redsn0w, or PwnageTool, you need to enter a pwned DFU Mode. During that process the software gets patched and the custom firmware should run without any problems.
- APTicket problems if you try to restore to iOS 5.x in the DFU Mode.
Error 1601 See also Apple’s Knowledge Base article number TA38633.
Error 1604 Device was not pwned (signature checks were not blocked). Custom firmware can’t be restored. Can also happen when there’s a problem with the IPSW.
Error 1611 iTunes tried to enter the Restore Mode, but the device turned back to the Recovery Mode. This can happen when updating an iPad 2 jailbroken with Saffron gets updated to iOS5. In this case simply retry, as it is in Recovery Mode then anyway.
Error 1618 Missing system files or corrupt data in iTunes installation. Try to uninstall iTunes, restart computer, install again. This error also occurs for iTunes in Windows 8 for reasons currently unknown.
Error 1619 iTunes is too old and couldn’t read the iPhone in Recovery or DFU Mode. Please update iTunes and try it again.
Error 1644 IPSW was moved during prepare with iTunes. Try it again and don’t move the IPSW.
Error 1646 iTunes expected the device to be in a different state (Example: booted into iOS rather than jumping to iBEC).
Errors 2000-2009 (from Apple support): 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 are 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 does not resolve the issue, try the USB issue-resolution steps and articles listed for Error 1604. If the issue persists, it may be related to conflicting security software.
Somebody reported that reinstalling the USB drivers fixed the problem.
Error 2006 Replace the USB cable with a newer one and/or disconnect all other USB devices, then retry.
Error 3123 Something dealing with movie rentals.
Error 3191 QuickTime may be corrupted. You must reinstall it before iTunes will work. Windows users, also try turning off Compatibility Mode for QuickTime.
Error 3200 You are trying to update to iOS 5, when infact, the IPSW file has only a Restore Ramdisk.
Courtesy of The iPhone Wiki.
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