im giving my mother my iphone 5 she currently has an iphone 4s i back them up on itunes constantly. i plugged the 4s into itunes and did a back up this morning then tried to restore the iphone 5 i keep getting an error message saying there is a corrupt file. i went into my itunes preferences and checked my itunes back ups for some reason for her phone there is only one from today and a year ago i deleted todays back up ad backed up the iphone 4s again im still getting an error message. is there anything i can do please help