Partition Modification

For Hackintosh Install

You need to be CAREFUL to manipulate partitions. You are at risk of lose all data. BACKUP IS DEFINITELY RECOMMENDED.

The Purpose: Make a 1GB EFI partition. (Enlarge it from 100MB.)

It is recommended to use Minitool because Minitool is quite robust on manipulating Windows partition, as Dortania's guide mentions. It can even move / resize the current Windows partition; it reboots by itself and its own mini OS will operate the task, then Windows boots again with a new partition size.

  1. Preparation
  2. Minitool on Windows
    1. Minitool shrinks windows partition.
    2. Minitool moves the windows partition backward by 901MB. So that you have 901MB free space in front of the windows partition.
    3. Minitool moves the Windows Recovery partition immediately after Windows partition. So that all your free space is located at the end of the disk. (otherwise somehow macOS installer eats this space as well as if it is macOS's .) Note: this is not an active partition, thus minitool just operates the task without reboot. but just in case, you can reboot and check whether it will reboot with no problem.
  3. gparted on Ubuntu.
    1. make a backup of /sda/sda2 by $ dd if=/sda/sda2 of=sda2. I don't know how important the contents of this partion is. Make a backup just in case.
    2. gparted
      1. move /sda/sda2 backward by 901MB, then you have a 900MB at the end of EFI (/sda/sda1).
      2. So that you can extend the EFI partition 1GB.
        3. gparted once reports an error, but it successfully boots up somehow, luckily...
      3. Note 1MB is for just a margin for dd.
  4. Minitool on Windows again.
    1. the failure of the extension makes the size of partition 330MB. Thus I re-did the task on Minitool with success.
Actually this last step seemes to have destoryed the EFI. It took time to fix it.
  • How to resize EFI partition.
  • How to make Win10 bootable again
    • First you need to do this; Dual boot system. (see post-installation.) This is for blue screen at Win10 boot.


    After First minitool Operation.
    Note: 901MB free space in between. (for EFI extension, which is necessary for macOS installation.)
    Note: 60GB free space at the end. (for macOS)


    All operation is done. :) Ready for macOS installation!
    Note: 1GB EFI partition and 60GB free space at the end for macOS.

    1. You need 210MB for EFI partition, which is normally 100MB if it was created by Microsoft Windows Installation.
    2. The EFI partition is immediately followed by Microsoft Reserved Partition, which is apsolutely necessary for Windows Boot.
    3. Windows System Partition will be followed by the Reserved Partition.

    Original Partitions.

    It means that
    1. you have to move (and shrink if necessary) Windows System Partition
    2. then move the reserved partition,
    3. then expand the EFI partition.

    The Partition done! Bigger EFI and Msftres was moved right.
  • Minitool Partition Wizard
  • Move Microsoft Reserved Partition to right

    Yes, you can move msr to another location with gparted, but you also will need to keep some conditions (described further), otherwise, Windows could not be booted.

    I explored which conditions caused boot failure using virtual machines. Here are the facts:

    What I did not tested is if it is possible to make it less than 16 Mib. If in gparted I moved a partition to the very end of the disk space, partition started displayed as 15 mb (I think the last sector is shorter than all other normal sectors) and after applying changes, it failed. Gparted refused to move that partition, because it does not know how to shrink "unknown filesystem".

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    20220916