Error message: Attempting to copy to the disk "Data" failed. An unknown error occurred (-54)
I got this error message "Attempting to copy to the disk "Data" failed. An unknown error occurred (-54)" while syncing my iPhone6 Plus (IOS 9) to iTunes 12.3.0.44 (64-bit) on Windows 7 / Outlook 2010. What does it mean? How can I fix it? Thanks in advance.
iPhone 6 Plus, iOS 9