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I replaced the Logic Board AND SSD of my Mid2015 Retina MBP. I’ve got a board from iFixit and used an Aura N SSD which is supported from Sierra on (El Capitan did not recognize the internal SSD but I was able to install to an external USB Drive) I managed to install Sierra. Upgrading from Sierra to High Sierra fails after a reboot with the “macOS could not be installed on your computer. An error occurred while verifying the firmware” message. How can I install macOS > Sierra? Model: MBP, 11.5 Boot Rom Version: MBP114.0172.B25 Thankful for any help!
There’s a few different issues you could be facing! The first is if you are trying to install High Sierra or Mojave Apple messed up the certificates pre-maturing expiring them! Here’s more If you’ve got an old macOS install image, it will probably stop working today Here’s the fixed installers: How to upgrade to macOS High SierraHow to upgrade to macOS Mojave If you where trying to install Catalina, there have been reports of problems with the updater. So its important to first upgrade in order through the releases and then go to Catalina. If that fails visit an Apple Store so they can fix it.