Today I did a clean re-install of Big Sur 11.2.1 because I messed up with my windows partition. I wipe my whole ssd in the bios and did a clean installation with my working EFI files.
I copy my EFI from my old system which is fully tested and make an installation USB based on it.
After installation I have three boot option in my bios:
1. Old EFI USB
2. New installation USB with same EFI
3. My ssd where the Big Sur was in, I put the same EFI folder into the EFI partition
However, now I can only boot by #2. Both #1 and #3 will give me black screen with single blinking underscore before the opencore boot picker. The blinking underscore will show up right after I exit the bios menu.
I have no idea where did I do wrong. Any suggestions?
Thanks!!!
I copy my EFI from my old system which is fully tested and make an installation USB based on it.
After installation I have three boot option in my bios:
1. Old EFI USB
2. New installation USB with same EFI
3. My ssd where the Big Sur was in, I put the same EFI folder into the EFI partition
However, now I can only boot by #2. Both #1 and #3 will give me black screen with single blinking underscore before the opencore boot picker. The blinking underscore will show up right after I exit the bios menu.
I have no idea where did I do wrong. Any suggestions?
Thanks!!!
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