So my 2011 macbook pro had the obligatory logic board failure last weekend and wouldn't get past the log-in screen. I received it back, with a new logic board yesterday and after swapping the SSD back ...
Cloned SSD won’t boot? Learn how to check BIOS boot order, UEFI/Legacy mode, BCD repair, SSD cloning issues, and boot ...
No idea why the SSD isn't listed as a boot option. The only thing I can think of is that the BCD on the 4TB drive isn't configured properly, or the boot files didn't get copied properly to the EFI ...