Update your Mac to the latest version of macOS to get the latest version of iTunes supported by your system, or get the latest version of iTunes on your PC. (With macOS Mojave, iTunes comes bundled with macOS.)
If you can't update to macOS Mojave on your computer, you might have to reinstall iTunes 12.8 on your Mac.
Reinstall iTunes 12.8
iPhone XS and iPhone XS Max require a Mac running at least OS X El Capitan 10.11.6 or later and iTunes 12.8 or later to sync and back up with iTunes.
To upgrade iTunes, use these steps:
- If it's open, quit iTunes.
- If your iOS device is connected to your Mac using USB, disconnect the cord.
- Download iTunes 12.8 from Apple and install it on your Mac.
- Unlock your iOS device, and while the home screen is visible, reconnect it to your Mac using USB.
- Open iTunes.
- When you see a message that says "A software update is required to connect to this [device]," click Install. Learn more about what to do when you see this message.
Get more help if iTunes still doesn't recognize your device.