I'm suspecting you encrypted your drive so it will only work in your original logic board as its keyed to the S/N of your system.
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I'm suspecting you encrypted your drive so it will only work in your original logic board as its keyed to the S/N of your system. It won't work with the replacement board.
Review this: [https://support.apple.com/en-us/HT204837|Use FileVault to encrypt the startup disk on your Mac]
You'll need to create a bootable drive so you can enter the recovery key to unlock the drive. If you lost it heres a way to regain it: [https://apple.stackexchange.com/questions/188991/obtain-filevault-2-recovery-key-with-administrator-account|Obtain FileVault 2 recovery key with administrator account]
And if you can't recover it - Ouch! [https://www.macworld.com/article/3192941/security/want-to-recover-a-filevault-encrypted-drive-without-a-recovery-key-youre-out-of-luck.html|Want to recover a FileVault-encrypted drive without a recovery key? You’re out of luck]
While you can undo file vault it will take some time! Your other option is to make a backup (un-encrypted) so you can wipe the drive down and re-install your OS and then recover your backup.
I'm suspecting you encrypted your drive so it will only work in your original logic board as its keyed to the S/N of your system.
Review this: [https://support.apple.com/en-us/HT204837|Use FileVault to encrypt the startup disk on your Mac]
You'll need to create a bootable drive so you can enter the recovery key to unlock the drive. If you lost it heres a way to regain it: [https://apple.stackexchange.com/questions/188991/obtain-filevault-2-recovery-key-with-administrator-account|Obtain FileVault 2 recovery key with administrator account]
And if you can't recover it - Ouch! [https://www.macworld.com/article/3192941/security/want-to-recover-a-filevault-encrypted-drive-without-a-recovery-key-youre-out-of-luck.html|Want to recover a FileVault-encrypted drive without a recovery key? You’re out of luck]
While you can undo file vault it will take some time! Your other option is to make a backup (un-encrypted) so you can wipe the drive down and re-install your OS and then recover your backup.