Chosen Solution
I was doing my school work and my browser needed to update. I did the update but when I tried to open it again, it showed that it was corrupted or the file was not found? Then I tried to open iTunes and the same thing happened too. I thought to reboot it but it just gave me the crossed out sign when I tried to reboot. I thought it was the hard drive cable (which I have replaced before) but I accidentally ordered the 821-1480-a rather than the 821-2049-a which is the one my Macbook had [I do not know if it makes any difference. I’m still very new]. During the process, I had chipped the flex cable (or gold ribbon cable) a bit and I do not know if that makes any difference in the world [picture shown below] After the installation of the cable, it no longer gave me the crossed out sign but just stayed on the Apple logo with the progress bar underneath it. My SSD was just fine and showed no signs of failure until that day. I even did the whole disk utility thing and Apple diagnostic tests and reads that there is no error. However, on the Disk Utility info, it said my drive was not bootable. I have a Crucial MX 500 250gb SSD Any help will be appreciated. Thank you. A picture for reference of the cable that was chipped
99% of the time it’s that HD cable; the 1% is a truly failed drive. Changing it cures the problem nearly 100% of the time on these. Refer to this guide for the part and this question for the patch points: Will Crucial MX500 2TB 3D CT2000MX500SSD1 SSD work in my Mid-2012 MBP?. DO NOT install it raw; that’s what ruins them. Did you upgrade to an SSD without upgrading the cable too? If you did, you found out why the advice towards people getting SSDs is to change the cable while they’re in the machine. Some of the Mid ‘12 machines got thin SATA II cables from the 2011 Pro, whilt others got a wider SATA II cable from when Apple revised it a 2nd time. Since there are 3 known revisions and 2 bad revions (one of which is hard to tell apart), it’s usually better to change the cable and know you have the current part in the system UNLESS THE SELLER HAS DONE IT.
