Without performing a block level sector by sector test of the HDD you can not say with authority that the HDD is bad however in all likelihood it probably is and why you should immediately backup any User Data that is not already backed up off of the HDD. After that if you want another method of preforming a block level sector by sector test of the HDD from a Terminal booted from the OS X Recovery partition, or a Disc or USB Device if you made one, then I'll tell you how to do it.
Message was edited by: WoodyZ Originally posted, May 30, 2013 2:09 PM> Added "not" after "is" before " already backed up..."