Hey! I have Macbook Pro mid-2012 model (A1278), it froze one day so I restarted it and got an empty folder with a question mark and that is the way it has been ever since when installed internally. I used an external enclosure and it works perfectly fine, so I know the SSD is not an issue. Would the SATA cable be the suspect then? That's all I could think of, but I wanted to know what other people thought if they had been through something similar themselves before I spent money on a new SATA cable.