I'm attempting to triple boot my MacBook Pro following this guide.

I successfully set up a Windows partition with Boot Camp and had rEFInd working.

However, I tried to install Ubuntu and now cannot boot into Windows 10 with rEFInd. I get the error BlInitializeLibrary failed 0xc00000bb.

I found this Microsoft support article but I'm not sure what it means for my situation.

What could the Ubuntu install have done to cause this and what can I do to fix this?

1 Answer 1


In case this is useful to someone out there... I'm typing this from a just-triple-booted 2015 MacBook Pro. I was stuck in the same place and this link saved me:


In short, whenever you use Ubuntu to change the partition table changes it from "Protective MBR" with GPT to "Hybrid MBR" with GPT which leaves Windows unable to boot. Using gdisk to restore it to "Protective MBR" fixes it. See the link for a complete answer. Here's a screenshot of the process as carried out in my terminal.

Also, you'll need to disable the SIP (See link. You do this by running csrutil disable in Recovery Mode.) in order to access the disk (/dev/disk0 in my case). Use diskutil list in macOS to see what's your disk's name. And do not use gdisk on partitions. It is meant to be used on disks.

Hope this helps.

  • Trying to dual-boot a macbook mid-2012 to windows +linux and your answer made it work!! Thanks!! Commented Apr 24, 2021 at 10:31

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