How to fix an unknown error occurred (1600) − iPhone, iPad, iPod touch

If the USB lightning cable was plugged to a USB hub when you got this error message, it is possible that the hub is responsible for it, as it doesn't establish a proper contact between your computer and your iOS device. This doesn't mean that the hub is broken, but there is an option that the one of the ports is not working correctly, or simply the hub doesn't know how to introduce the iOS device correctly.

It is recommended that you should always plug the USB cable directly in one of the computer's USB ports, as sometimes iTunes might not recognize the device directly.

Plug the USB lightning cable directly in one of the computer's USB ports and try again.

Sometimes, an older iTunes version can cause the error 1600, because it isn't in sync with the latest operating system updates, or with the latest changes Apple made. In this case, all you need to do is to update iTunes.

Aside form downloading it from Apple's website, you can update iTunes to the latest version via iTunes itself, by following the steps below:

1. Open the iTunes app;
2. Click on Help and select Check for updates.

The computer drivers are the communicators between the operating system, and the computer hardware. Among their numerous benefits, thanks to them, moving the mouse physically, the mouse pointer is moved on the computer. Outdated drivers can also be responsible for the "an unknown error occurred 1600" error message in iTunes, which may cause the computer not to recognize your iOS device properly.

Updating the computer drivers is all you need to do to fix the issue. Also, it's an imperative to update them to the latest versions frequently, so that you ensure that other pieces of software can function properly, and will not interfere in other processes.

The easy-to-follow how to update drivers guide will assist you, if you are not sure how to update drivers.

Stable Internet access is needed for almost every operation you do with your iOS device, as files needed for updating or restoring your device are downloaded from Apple's servers. In case if the Internet connection is unstable the downloaded files may get corrupt, causing issues when you try to install the files.

Ensure that your Internet connection is reliable and fast before performing any action with your iOS device. Also, tips to improve the stability of your Internet connection include:

• Bring your router closer to your computer;
• Buy signal boosters;
• Upgrade to a stronger Internet provider.

There is a tiny possibility that an outdated antivirus software is the reason for the iTunes error 1600, as it mistakenly believes that your iOS device is not safe and poses a threat. Check the quarantine menu of your antivirus software. If you find a note regarding your iOS device, or iTunes, all you need to do is to remove them (restore them). 

If your antivirus was indeed blocking your iOS device, check if an update to your antivirus software is available, by visiting the developer's website and if it is, apply it. By applying the update you will also gain access to the latest antivirus software database of threats.

Another more frequent reason for error 1600 is a bad link between your computer and the iOS device. Make sure that you plug in the lightning cable properly, on both ends, every time you want to exchange data, update or restore your device, as the gold plates of the lightning cable need to touch the respective gold plates of both your computer and iOS device.

If you get the an unknown error occurred (1600) error message, and you don't have the time to address it, or you don't know where to start from, consider contacting Apple's support staff and they will help you diagnose and fix the issue.

You can contact their team online, via getsupport.apple.

If restoring your device using another USB cable worked, this means that your USB cable was defective. As fixing it is next to impossible, the best course of action is to replace it with a new one.

Note: Make sure to buy a new USB cable from authorized Apple resellers, as fake USB cables can be responsible for a wide range of issues, too.

If you tried all the other options to fix this issue, including plugging in your device to another computer, even with a different USB cable, but nothing worked, consider taking your device to a repair shop so that they can investigate this issue further and address it.

It is possible that the current firewall and/or antivirus settings are causing this issue. To test this, try disabling them first and check if you still get the error message.

If you don't get an error message, access the firewall and the antivirus settings and check how they are configured, consulting with help articles which can be found on the developer's website or in the operating system.

To disable the Windows Firewall:

To enable the Windows Firewall:

Consider restoring your device from DFU (Device Firmware Update) mode as a last resort, as it involves data loss, and only if you are 100% sure that there is nothing wrong with the USB cable and the computer. The procedure would be the following:

1. Put your device into DFU mode - consult this article on imore, if you are not sure how;
2. Connect your device with your computer, via the USB cable;
3. Restore your device, following the on-screen instruction on your computer.
   
   

Note: If you use a laptop, make sure to plug it in a power outlet first, as interrupting the restoration process is not advised and can be dangerous, and even damage your device.