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I have the A1708 Retina with 256 SSD. I was wanting to update the SSD to 1tb. When I installed the new drive with the adapter the computer will not see the drive!! So I replaced the original ssd and then the same thing happened. The computer can not see the boot drive. Please help me. ??
When you say it won’t see the drive are you trying to format it and install a fresh copy of macOS using Internet recovery? Reference: About macOS Recovery on Intel-based Mac computers
