Hi MacRumors! I have a quick question that you might be able to assist me with. I have a MacBook Pro 13 Inch Early 2011. I recently moved my HD that came with my computer to my optical bay and purchased a OCZ Vertex 4 SSD to put in the HD Bay. I placed the OCZ Vertex 4 SSD into an external USB HD holder and it was recognized properly. I then installed 10.8 on the SSD via external USB and booted up fine. After moving some files and setting everything up, I installed the SSD into my actual computer where my old HD was installed. I then booted up only to find when I held down option key on startup that the SSD wasn't showing up. I booted up to my optical drive (where my old HD is) and, opened up disk utility to only see that the SSD is not showing up anywhere. I opened up my macbook again, and made sure everything was properly connected, which everything is. Why is my SSD showing up via an external HD holder but not when it is placed inside my actual computer? What can I do to fix this issue? Thanks for any help, I truly appreciate it!