Apple iPad error 14
Apple has launched the first beta of iOS 10 registered developers, which offers new features and significant improvements. Users reported that they encountered an error message 14 in iTunes when they tried to update their operating system to iOS 10 Beta 1. The problem occurs when they update their operating system on newer while performing a restore from a backup. This was possible until iOS 9, but with iOS 10, it seems like you can not do both at the same time. To solve the problem of iTunes 14 error on your iPhone, iPad or iPod Touch, here are some solutions that you can try.
Solution 1: Check Your USB Cable
The iTunes 14 error may occur when you have a USB connection problem. Try another USB port on your computer or use another USB cable. You'd better use the original Apple Lighting USB that came with your device. And you can send the USB cable via SMS to another computer.
Solution 2: Restart Your iDevice and Computer
This is a simple way to solve the iTunes 14 error problem. You can often forget about it. You can always try to restart your device when you have a problem.
Solution 3: Backup and Try Clean Restore
Start by backing up your device, and then perform a complete restore of iOS 10/11. Then, perform a complete restore of iOS 12 using the IPSW file downloaded from the Apple Development Center. Finally, restore your device with the backup you created after installing iOS 12 successfully.
Solution 4: Install the Latest Version of Xcode 8
Access the Apple Developer Web site to download and install the latest Xcode 8 on a Mac computer. Apple says: You must have the latest version of Xcode 8 installed on your Mac before using a recovery image to install the iOS or tvOS beta software on a device. So make sure the latest version of Xcode is installed on your computer to avoid or fix iTunes error 14.
Solution 5: Update iTunes to the Latest Version
Apple has always released the new version of iTunes to work with the new operating system. So go take a test and update iTunes with the latest version.
Solution 6: Turn off Security Software
If you have security software installed on your computer, you can disable it first, and then try to update and restore your iPhone / iPad again. If you still experience the iTunes 14 error, you can uninstall the security software.