MacBook Pro 2012 mid mod Hi, I just changed my hdd on my mac because it was very slow so i replaced it with a ssd. The lion operative system didnt read my ssd so i made a bootable El capitan OS X on my ekstern hard drive. when i booted it i saw the ssd once but when i restarted the mac it was gone. i have tried everything. How can i make the system to show my new ssd ? please help. Thanks.