MacOS Boot Option Missing After Boot Camp Install

Question

Level 1

37 points

MacOS Boot Option Missing After Boot Camp Install

I have a booting issue with my 2009 Mac Pro. I recently installed Windows 10 through Boot Camp. That worked fine. Now, I'm having troubles trying to get back to Mac OS after running Windows 10. "Mac OS X" properly shows up twice in the Boot Camp Startup Disk within Windows. It's there twice from my main partition and a Time Machine partition (I assume). Selecting either does not work and just boots back into Windows 10. Booting with the option key held down only yields two options - "Windows" and "Recovery 10.11.2". The Mac booting options are gone!

So far, I've only tried to run "First Aid" on the hard drives through the recovery's Disk Utility program. No luck. For what it's worth, File Vault is not being used.

How do I get my Mac booting option back and keep this from happening again?

Mac Pro, macOS Sierra (10.12.6)

Posted on Oct 4, 2018 1:22 PM

Reply

Answer 1

Best reply

eeboarder Author

Level 1

37 points

Oct 4, 2018 4:42 PM in response to eeboarder

I fixed it, kind of.

I booted from a Mojave USB drive and used the Disk Utility in that installer to repair and mount the drives. My RAID is still not accessible, though. I'm looking into it.

FWIW, the OS version is 10.11.6.

Reply

Answer 2

eeboarder Author

Level 1

37 points

Oct 4, 2018 2:18 PM in response to Loner T

It's either 10.11 or 10.12, whatever the last supported OS was for an early 2009 Mac Pro. I don't exactly recall, but it does not have the networking option when selecting the boot drive after holding down "Option" at start up.

The article does not help much. I do not see any of my Mac OS drives available when booting to the "Startup Manager".

Reply

Answer 3

eeboarder Author

Level 1

37 points

Oct 4, 2018 3:08 PM in response to Loner T

I did the NVRAM reset. It acted like it was going to boot into Mac OS with the Apple logo and progress bar, then went to the recovery mode. In recovery mode, it said "Installation Failed" with a very long log. Odd.

Here is an output for diskutil list. I have four internal hard drives. The primary is shared with Boot Camp, second is a Time Machine backup, the last two are RAID'ed for media.

I could not add a photo directly, so here is the imgur link.

Imgur: The magic of the Internet

Reply