Restore unknown error 53
My Touch ID stooped working the iStore people advised me to reset the settings, after that failed to resolve issue, they said to restore the phone to factory. I plugged it into iTunes on my computer, did the latest back up, downloaded the latest software and then clicked restore. It was telling me that iTunes is preparing for iPhone restore for a while before I got the error: "Your iPhone could not be backed up due to unknown error (53)". I have tried restarting my computer and even used a different computer since I couldn't switch my iPhone on, I keep getting the same error.
Does anyone know what I can do and how long it'd take to get my phone back if I take it into the iStore?
iPhone 6, iOS 8.2