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I have a mid 2012 Macbook Pro 15”, a few years ago I replaced the HDD with an SSD and replaced the optical drive with the original HDD that was in the computer using the OWC data doubler. It all worked well but then last week I started having problems with the secondary drive, whenever I tried to copy large files over I kept getting the error: “The finder can’t complete the operation because some data in can’t be read or written”. I looked up what the problem might be the everything seemed to suggest that the drive was going bad so I bought a new drive and put in into the computer. Then when I tried to format it I got this error: ”Wiping volume data to prevent future accidental probing failed.” I looked up what the problem might be again and I found out that the MacBook Pro mid 2012 doesn’t support SATA III (6.0 Gb’/s) in the optical drive port and that I would need to get a SATA II (3.0 Gb/s) HDD. So I did but I’m still getting the same error. The only other solution I’m seeing is to replace the SATA cable but how do I do this for the optical drive? Do I have to replace the whole data doubler? Exactly which cable do I replace? Whenever I look it up I just find a replacement for the original hard drive cable but nothing on how to replace the optical drive cables.
I don’t think your issue is the optical drive SATA cable Unibody Macbook Pro 15" Optical flex cable (09/10/11/12) Your issue is the HD SATA cable! MacBook Pro 15" Unibody (Mid 2012) Hard Drive Cable. While you are focusing on prepping your optical drive mounted drive. The OS drive (HD bay) still needs to be functional for the process to work properly. OS installs are quite I/O intense so any slight error in the cable just magnifies the issue. There are a few things that you should do to help protect the cable the first is protecting it from the rough surface of the uppercase. You need to apply a strip of electricians tape on the uppercase where the cable crosses over. The second issue is the bends around the corners, here we need to form the bends in a smooth arc as a sharp crease will damaged it! I use a BIC pen ink straw (a bamboo cooking skewer will also work) to shape the bends so the bends are a nice radius arc. While that fixes the root issue. You still have a second issue, thats the SSD has errors on it which will need to be fixed. The best way is to first backup your apps and data thats on the SSD. Using an OS installer drive to reformat the drive and install a fresh copy of the OS back on your drive. I do strongly recommend you leave at least 1/4 and if you can 1/3 of the drive free so the system is able to leverage it for virtual RAM, caching & page files for your OS and Apps. Depending on your Apps you might want to alter the scratch space to point to the SSD as well. Leaving all of your data on your other drive.
