One of the main causes of Error 4000 is the device being locked during the update process, which interferes with iTunes’ ability to update the iPhone. Other potential causes include outdated iTunes software or problems with the USB connection. Now that you understand the problem, we will move on to the solutions. Before proceeding with troubleshooting, it’s important to keep your iPhone unlocked during the update process to prevent Error 4000. Here’s how you can do it: Once the update is successful, you can reset Auto-Lock to your preferred time setting. If the problem persists, you can try to download the iPhone update directly from the Software Update section on the mobile. In some cases, the error is triggered if iTunes is outdated. Therefore, it is recommended to update your iTunes application to the latest version.
