Let me tell you the entire story I was playing League of Legends with my friends, we just started the game and my screen froze on the pre game loading screen, it was completely frozen and my only option was to manually shut it down. When I shut it down, the apple logo would appear and the laptop would immediately shut back down. Starting it up in safe mode wouldn't work either. I then tried Command R to try to repair my disk and it said that my disk was damaged and needed to be repaired (I had 10MB free on my disk). Now, i realised i had 500 GB of junk on my computer and i understood that keeping it and backing it up would be pointless so i just erased my disk, i did this because reinstalling Mac OS wouldn't work. When I erased everything on the disk it still wouldn't work, the operating system just didn't want to install it said that my disk was damaged. I then decided to try to repair my disk ( i did the partitions ) and try reinstalling the operating system, same problem occurred. That's when I decided to pull out a 1 terra hard drive i had, entirely format it and install Mac OS on it. I am currently running Max OS X Version 10.9.5, here are my specs ( i am currently running mac on a western digital "My Passport") : MacBook Pro 13-inch, Mid 2012 Processor 2,5 GHz Intel Core i5 Memory 4 GB 1600 MHz DDR3 Graphics Intel HD Graphics 4000 1024 MB Software OS X 10.9.5 (13F34) I just wanted to know what i could possibly do to be able to use my internal hard drive, any help would be appreciated I just want to climb the League of Legends ranked ladder. Thank you very much and sorry, this is my first post on this forum.