Would love to share this with you.
I got this error several times and looks like iTunes software stuff things up.
To get around this error do the following
- Shut down and unplug your iPhone or iPad or iPod.
- Quit iTunes Software.
- Plug in your iPhone iPad or iPod.
- Open iTunes if it does not automatically open.
- It should start to sync now If not then.
- Shutdown your iTunes software and Open it again without unplugging your iOS device.
The above steps worked for me and I am sure they will work for you too.
Another thing that you can try if the above fails is to take a snapshot of your Backups and then delete them all. Your backups are generally located here
After deleting the Backups try your sync again. BUT please take a backup of your Backups before deleting them