Chosen Solution
iPhone sync to laptop invalid response
I’d start by making sure the port in the phone is clean from any lint, then use a known good cable, while trying to sync with the latest version of iTunes as some older versions do not sync with newer iOS / iPhone software versions.
Try connecting your laptop to iTunes on a PC, Connect via USB cable. Sign in to your iTunes account. When your phone appears on the screen that has the Back up, & restore buttons on it, scroll down and give it permission to sync, and sync it there. also, you might try clicking on the preferences tab in top left corner See if you see where you need to click to allow to have permission to sync
