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I use a 1tb external drive for my Macbook Pro. I got it as a gift and the hard drive isn’t detected no matter what I do. It’s a 250 gb Samsung SSD and it won’t detect it. I have tried a different drive and even a new flex cable but neither have worked. Can somebody help me out?
Formatting! What system is your external drive and internal drive running? How are they formatted, APFS vs standard GUID? UPDATE 4/16/20 Upgrade your Lion disk gradually thru the systems as there is probably an EFI Firmware update that your machine has missed
