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I've just reinstalled Sierra after a partition resize nightmare. I wiped and restored from Time Machine and repartitioned again but haven't reinstalled Windows yet.

As seen below there is a suspicious MBR at sector 0. Is there a way to fix it?

As shown here

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That's a hybrid MBR. It's necessary to boot Windows in BIOS mode, but if you plan to install Windows 8 or 10 in EFI mode, you need to replace the hybrid MBR with a legal protective MBR. You can do this with my GPT fdisk (gdisk) program:

  1. Launch gdisk on the disk (sudo gdisk /dev/disk0 in your case).
  2. Type x to enter experts' mode.
  3. Type n to create a new protective MBR.
  4. Type 'w` to save your changes.
  5. Type y to confirm that you want to save the changes.
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  • To the anonymous editor which made a suggested edit that indicated EFI mode is required to be enabled if you want to run Windows 8 or Windows 10. You are wrong. Hopefully you don’t go around spreading this information, because it to put it simply, false information that confuses new Windows users.
    – Ramhound
    Commented Dec 5, 2017 at 23:50
  • This just saved me a lengthy re-install and re-setup of a machine that got damaged during a partition resize. THANKS!
    – rsp1984
    Commented Jun 8, 2018 at 18:04
  • Worked for me too! The above steps immediately fixed my issue where Windows would no longer boot after I resized its partition. Rod you're awesome.
    – electromaggot
    Commented Mar 23 at 19:20

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