Hello. I need to upgrade the firmware on my Mac Pro 2010 in order to be able to update from Sierra to High Sierra. All the instructions I've read tell me that the firmware update is contained in the High Sierra installer package, but the update does not work when I run the installer. I am looking for a way to update the firmware separately from the High Sierra installation process. Do you have a firmware download solution for this?
You can download the firmware update separately from Apple's website. Here's the link: https://support.apple.com/kb/DL1321?locale=en_US. Follow the instructions provided and the firmware update should install successfully.
Question. Ability to boot to High Sierra is good, but is there any downside to upgrading the firmware from MP51.007F.B03 to MP51.0089.B00? Will I still be able to boot to, say, Lion?