Solved Why Won T The 1Tb Hd Accept Os 10 12 Sierra Macbook Pro 15 Mid 2012 Ddr3

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How do I reformat the SSD to a GUID Partition Table Scheme when it’s not a option in the Disk Utility?

you need to boot into recovery mode and use disk utility there. you cant use the erase function, you need to use the partition function and change it to 1 partition mode and click the options button and choose GUID