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Boot Yosemite / Windows 8.1

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Hey guys,


last problem to solve for me: I want to boot Yosemite or OS X with Clover. Both OS are on the same hard disk which is formatted as GUID. Yosemite is OS X Extended (partition 2) and Windows NTFS (partition 3). Partition 1 is EFI.

I tried several things without solving this problem. The NTFS.efi (?) is inside the driver64 folder. Yosemite starts fine but if I want to start windows, after a short time the message "a disk read error occurred" appears.


So can somebody help me, please? What I have to do to solve this?


Thank you :)

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as it's a GPT Parition .. you will need to follow a guide of installing windows 7 on a UEFI Parition


there is tons of guides here you will need to search



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I followed this guide:

/edit: Sorry that I have to disturb you again, but I don't get it  :( I tried several guides but Windows 8.1 does not want to start.

This is my current configuration, GUID, OS X has Mac OS Extended Journaled, Untitled (Windows 8.1) has NTFS, both OS on my SSD. EFI partition is active set by Windows 8.1

This is my folder structure in the EFI partition of my SSD

If I start My system, I can choose following devices to start

I'll take SSD (M4) and has following options to start.

If I choose the one option of the picture above, I get this error

If I choose following option, After some time with following icon I get this error.

Please I need your help, I despair  :(

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No one? Copying bootx64 file to /EFI/Microsoft/Boot and renamed it "bootmgfw.efi" does not solve this problem..

I want to install OS X one the first partition, Windows 8.1 on the second partition. Clover should be install in EFI partition of disk 1 (SSD). After installed Windows, my notebook only boots in Windows. So I defined the EFI partition as active and now Clover boots - but only in OS X, Windows does not work (as I explained in my post above). I make anything wrong but I don't get it.

GPT should work, I used it in Chameleon, too (and I only had to install Chameleon and it worked - always!).

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You need to repair your Windows 8 UEFI bootloader.


Create a UEFI Windows 8 USB installer or Recovery Disk and use it to boot into a command prompt.  Follow the directions in this post from @Alex to restore the UEFI Windows bootloader and rebuild the BCD store in the EFI System Partition using the bcdboot command:

bcdboot c:\Windows /l en-gb /s b: /f ALL

where c:\ is your Windows volume, b: is the letter assigned to your EFI System Partition.


After the repair, reboot the computer normally to Clover on the the hard disk

----> choose "Boot Microsoft EFI Boot Menu from EFI"

---->then select bootmgfw.efi from the submenu to boot (hopefully) into your newly repaired Windows 8.


Good Luck!


PS: That Niresh Guide is misleading and in fact gives instructions for dual booting OSX and Windows in legacy (hybrid/MBR) mode. 

If it has a "hybrid" MBR, use GDisk to write a new "protective" MBR on your SSD ---> ensures the disk is pure GPT and can install UEFI Windows for best compatibility with Clover.


Download GDisk, Man page for GDisk.

@pokenguyen's AIO guide

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