I have a MacPro 1,1 that's been running Yosemite for several months now. I replaced the stock ATI x1900XT graphics card with a generic GT640 when the ATI card died, so I don't see any graphic output until the desktop shows up. This can make debugging startup problems difficult!
This post is just in case anybody else finds themselves in the same boat I was in.
Today I upgraded from 10.10.1 to 10.10.4 today and forgot to preserve my boot.efi. I was able to fix it by doing this:
1) I took the boot SSD out of my MacPro and put it in another MacPro that's still running Snow Leopard.
2) I download PikeYoseFix from post 2166 of this thread.
3) I extracted the pkg file ("xar -xf archive.pkg") and extracted the contents from the Payload file ("cat Payload | gunzip -dc | cpio -i")
4) I copied the boot.efi from the archive to the two locations on the mounted SSD:
Code:
sudo chflags nouchg /Volumes/mydrive/System/Library/CoreServices/boot.efi
sudo cp boot.efi.pike /Volumes/mydrive/System/Library/CoreServices/boot.efi
sudo cp boot.efi.pike /Volumes/mydrive/usr/standalone/i386/boot.efi
sudo chflags uchg /Volumes/mydrive/System/Library/CoreServices/boot.efi
5) After putting the SSD back in my MacPro 1,1, the computer would unfortunately still not boot. I could tell it wasn't even starting the boot process because if I pressed the power button, it powered off instantly (no waiting for a safe shutdown or anything like that).
6) I had to bless the drive. From the Snow Leopard MacPro, I ran:
Code:
sudo bless --folder /Volumes/mydrive/System/Library/CoreServices/ --file /Volumes/mydrive/System/Library/CoreServices/boot.efi
7) I put the SSD back in my MacPro (again), and it booted! I still had no video, but I VNC'ed in, watched the 10.10.4 installer finish up, and then restarted one more time. After this restart, all was well, and I could use my computer again.
Lesson learned!