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Dual-booting Windows 8 and Mountain Lion natively using EFI

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This is NOT about installing Windows 8 on a Mac, this is about using Apple’s EFI to boot Windows.

(If you don’t know what an EFI is, see Wikipedia)

Okay, so here’s what’s going on:

Apple has used EFI to boot OSX for years, but Windows has not supported this method of booting.

With Windows 8, Microsoft claims that you can boot with EFI so long as the drive you’re booting on has an efi partition and uses a GUID partition table.

Here’s the kicker, for years now, OSX has been using a Hybrid MBR partition table… that is they are using a GUID partition table with a matching MBR partition table embedded into it. This means that older versions of Windows can see the partition information from the older MBR system and will work properly using a legacy bootloader. But if you have an EFI installer for Windows, it will not let you install (or even BSOD!) if you try to use it as it sees the MBR and ignores the GUID.

A lot of posts online cite that Apple’s EFI implementation is based on EFI v1.1 and that Windows supports only EFI v2 and newer. This is NOT the case. It doesn’t work because the Windows installer sees the MBR in the hybrid partition table and decides that you are NOT using a GUID partition table even though you are.

Luckily, there is a way around this to get a fully native EFI-booted Windows 8 installation! But beware, this path (while awesome) is paved with daggers, so be prepared to pull your hair out in frustration.

Warning: These steps require you tocompletely  erase your hard drive! Make sure you have all the materials and have backed up all of your data before proceeding.


  • A recent MacBook Pro (this will probably work on other Macs, but I don’t have any to test with) I’ve tested this on the 1st-gen Retina 15″ and a 13″ 2nd-gen i5 model.
  • A disk drive capable of reading DVDs (you’ll need an external drive for MacBook Retinas or MacBook Airs)
  • A Mountain Lion Install Disk or Netboot Installer
  • A CD/USB drive with the “Windows Support” files from Bootcamp
  • A Windows 8 Pro Install DVD


  1. Put the Windows 8 Disk in the disk drive
  2. Option-boot the computer and choose to boot off the “Windows” disk (Do not choose “EFI Boot” but make sure that it does show up, you’ll need to use it later)
  3. Once the installer gets to the setup screen, hit shift+f10. This will bring up a command prompt
  4. Type the following commands (this assumes that you only have one hard drive):
    1. diskpart (this puts you into the windows partitioning shell)
      1. select disk 0 (this selects the primary hard drive, make sure you don’t have any extra drives connected)
      2. clean (this erases your entire hard drive by removing all partition information)
      3. convert gpt (this converts your hard drive from an MBR partition table to a GUID partition table)
      4. create partition efi size=200 (this creates the efi partition where the bootloader will live)
      5. format fs=fat32 (this formats the EFI partition as fat32 so that Windows can write to it)
      6. create partition msr size=128 (this creates a “MicroSoft Reserved” partition… because microsoft)
      7. create partition primary (this uses the rest of your free space to create a usable partition)
      8. format fs=ntfs quick label=Windows (this formats the Windows partition and labels it as “Windows” which is what OS X will see)
      9. exit (this exits the windows partitioning shell)
    2. wpeutil reboot (this tells the computer to reboot)
  5. Option-boot the computer when it reboots, but this time choose “EFI Boot” instead of “Windows”
    1. Remember to press the any key to boot into the installer!
  6. Choose to use a Custom Install and install Windows 8 to “Partition 3″ (The only primary partition)
    1. Make sure you leave the install disk in the drive through the whole install or you could get a BSOD
  7. Install the Windows Support software from your CD/USB drive to gain full functionality of your computer
    1. Congratulations! You now have a natively-EFI-booting Windows 8 Install! Now, on to dual-booting OSX…
  8. Open “Disk Management” in Windows.
    1. Find your “C Drive” partition and resize it by right-clicking on it and choosing “shrink volume”
      1. Shrink it by the size you’d like your OSX installation to be. ie. if you want to give OSX 100GB, use 102400MB
    2. Right-click on the now empty area at the end of the drive and make a new “Simple volume” Don’t format it.
  9. Reboot the computer into your OSX install disk/Netboot
  10. Open Disk Utility
    1. Choose “disk0s4″ as this will be the 4th partition on disk 0
    2. On the “Erase” tab choose “Mac OS Extended (Journaled)” since this is what OSX likes to use.
    3. Give it a label that you like (Apple defaults to “Macintosh HD”)
    4. Hit Erase
    5. Exit Disk Utility
  11. Install OSX on your new partition.
  12. Congratulations! You are now dual-booting OSX and Windows in a 100% EFI environment! Happy computing :)

Note 1: If you get a BSOD during install, make sure that you have NOT removed the Windows 8 install DVD from the disk drive… during install, removing the DVD at any time will produce a BSOD even though the OS no longer needs the disk to install.

Note 2: Windows now shows up in option-boot as “EFI Boot” instead of “Windows”

Note 3: Because we created the partition that OSX uses in windows, it no longer shows up in “My Computer” in Windows… Here’s how to fix that:

  1. Open “Disk Management”
    1. Right-click on the partition that you created for OSX (it should be labeled as an HFS partition)
    2. Choose “Change Drive Letter and Paths”
      1. Choose “Add”
        1. Assign it to a drive letter of your liking… I used “E”
        2. Hit OK
      2. Hit OK again
  2. You now have read-only access to your Mac Partition!

Update 1: I’ve been informed that for some models the sound does not work in Windows when booted via EFI. It appears to affect models that use the Cirrus audio controller. I’ve gotten ahold of a test unit and will see if there’s a workaround.

Update 2: Added formatting into step 4 to resolve possible BCD-related problems.

Update 3: Added “select disk 0″ to step 4, you can’t do anything if you don’t specify the disk.

Written by David

January 18th, 2013 at 12:51 pm

Posted in EFI,OSX,Windows

Tagged with , , , , ,

124 Responses to 'Dual-booting Windows 8 and Mountain Lion natively using EFI'

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  1. You don’t have to erase anything if you’re already dual booting Mountain Lion and Windows 7. Just use the Windows 8 DVD to update Windows 7.

    Andrew Pennebaker

    18 Jan 13 at 5:01 pm

  2. Unfortunately, that uses the legacy bootloader NOT EFI


    18 Jan 13 at 5:05 pm

  3. Doesn’t quite work on and early 2011 15″ MBP, partioning goes fine, boots the installer via DVD efi but gives a ‘cannot update boot configuration’ at the end of the file copy process. Ouch!


    31 Jan 13 at 8:47 am

  4. Does using native EFI booting allow to see and use both graphics cards (Intel & NVidia) under Windows (unlike Boot Camp)? How do you switch between them?


    21 Mar 13 at 4:57 pm

  5. My current test unit only has the Intel graphics, so I don’t know if it allows the user to see both cards. Since booting under EFI gives windows the same access to the hardware as OSX I would imagine that it is possible. However, it would probably be up to NVidia to make sure that the graphics driver can switch between discrete and integrated.


    23 Mar 13 at 3:38 pm

  6. Deefa, Please send me your model identifier (Macbook X,Y). I’ll try to get ahold of that model for further testing.


    23 Mar 13 at 3:42 pm

  7. FWIW, as long as software can use the integrated graphics’ feature (specifically, Intel Quick Sync Video), I don’t mind and/or care if both cards are enabled at the same time.

    Also, I should clarify that I am using a late 2011 MacBook Pro (Intel HD 3000, AMD Radeon HD 6570M) – I only mentioned NVidia as I assumed your hardware was the 15″ w/Retina model.

    BTW, I had the same error as Deefa, though perhaps not due to the same cause (attempting to EFI install on an external drive connected via Thunderbolt).

    I never tried an EFI install on the internal and went straight to Boot Camp because I didn’t care to image and then restore my OS X install, but I guess the Thunderbolt drive maybe wasn’t the issue after all.


    24 Mar 13 at 5:01 pm

  8. On another subject, is there any reason EFI Boot from the Windows 8 install disc can’t be used to call diskpart, avoiding one reboot?


    24 Mar 13 at 5:04 pm

  9. Yes, the reason for the initial boot being from a non-efi boot medium is because the hybrid mbr that Apple is using will cause the efi-booted install disk to crash before it gets to a usable point. By using the non-efi boot to format the drive as GPT you alleviate that problem.
    As for the Retina, I’ve had to return the device to Apple several times for screen-related problems (image retention… it’s really bad) since I wrote this post. So it is not currently set up like this (just haven’t had the time)


    25 Mar 13 at 1:10 am

  10. Would the above proceduce work with Windows 7 64 bit, as well?


    26 Mar 13 at 12:09 pm

  11. Hi, just installed on a Macbook Pro 5,2 (Unibody 17″ early 2009)

    Everything works with latest bootcamp drivers in Win 8, except I can for the life of me figure out how to install the NVIDIA drivers.

    GPU’s are geforce 9400m & 9600m GT

    But drivers from website won’t install as i assume the base number for these chips are different.

    Don’t suppose you have any idea?


    28 Mar 13 at 1:08 pm

  12. Adrian – It may well work with Windows 7 64-bit. My attempts to make it work a few years ago did not work, but that was using a different procedure than the one I created for Windows 8. As of now this procedure is untested with Windows 7 64-bit


    28 Mar 13 at 5:15 pm

  13. d00ski – I’m assuming you tried this driver: ? I don’t have any 17″ models to test with, but I may have access to a 15″ with the same configuration sometime in the next week if your problem persists. It would also be helpful if you posted the hardware ID of the 9600 card (from the Device Manager in Windows).


    28 Mar 13 at 5:19 pm

  14. I sure have. I even used laptop2go drivers with custom inf files.

    I’ve tried installing using the have disk method, and via the software setup.exe from nvidia. Also windows update is no help.

    I then went a bit extreme and tried installing the drivers by advance restarting win 8 without digital driver signing (the driver finally installed, but screen went black and eventually the computer rebooted with a problem has occurred message and driver remove. Back to basic WDDM 1.2. My problem is that there are many pixel on the screen that don’t render, simply because I can’t get a correct driver to install.

    Here are the device instance paths for the GPU’s:

    geforce 9400M

    geforce 9600M GT


    29 Mar 13 at 7:54 am

  15. I did this on a Mid 2010 Mac mini server (2 hard disks). I booted from a Windows Server 2012 install USB flash drive. For some reason, it only appeared in the options boot menu as EFI (there was no Windows boot device icon). I ran diskpart from the EFI-booted session – no crash. The Windows installation completed successfully. Audio worked after installing the Cirrus driver from the BootCamp 5.0.5033 driver set. I could not get any version of the NVIDIA GeFore 320M driver to work, but the Microsoft Basic Video driver, which was installed automatically by Windows setup, did work. The full 2660×1440 resolution of the monitor was displayed. I manually ran the following installers in the BootCamp 5.0.5033 driver set:AppleRemoteInstaller64.exe and AppleNullDriver64.exe. I added the RealTimeIsUniversal=1 value to the registry.


    3 Apr 13 at 6:27 pm

  16. Hi David,

    Did you manage to have a look at my driver issue?


    6 Apr 13 at 2:03 pm

  17. Hi,

    I’ve followed your instructions and get installed WIndows 8 Pro 64Bit.
    Thank you for this guide :-)

    As expected my sound card does not work…

    My Hardware: MacBook Pro Retina, 15-inch, Early 2013

    In Windows 8 64Bit you are able to see both VGA Cards.
    The NVIDIA GeForce GT 650M and the Intel HD Graphics 4000.
    But only the NVIDIA Card runs all the time, so the battery runs dry very fast.

    At the installation reboots I had to remove the USB Stick and plug it back in, otherwise the stick would not detected and the Mac crahes with a BSOD.

    I think the boottime is much shorter than with BootCamp. Is that my subjective impression or a fact?

    Many regards :-)


    25 May 13 at 3:34 pm

  18. I’ve been trying to get Windows to boot with UEFI on my Macs for years.

    If I only need to run Windows (without an OS X partition), do I have to go through all the bells and whistles? I just tried with a 2011 Mac mini (using a FAT32 USB stick with Windows 8 installation files), installed using EFI boot, and Windows boots only about 50% of the time. When it boots it shows a blank screen, when it doesn’t it shows a 0x00000001 error and restarts itself.

    Any pointer would be appreciated =)


    31 May 13 at 12:43 pm

  19. Dear Jim,

    do you finish the Installation process without problems or do you get the bluescreen at the reboots of the Installation process?

    If the problems appear at the installationprocess, remove the USB Stick / USB DVD drive quickly as soon as the mac reboot with the grey screen an plug it back in.

    In my case, the macbook does not recognize the USB Stick after every reboot (that happens also with USB HDD’s).

    Good luck :-)



    31 May 13 at 11:21 pm

  20. I’ve got the same problem as Deefa with the “cannot update boot configuration” on a mid 2010 MacBook Pro.
    Did you ever get a hold of a similar system and get Windows 8 to boot natively using EFI without that error?


    13 Jun 13 at 1:03 pm

  21. Im using a mid 2012 macbook air 13′

    Im stuck at a black screen after first boot attempt, the system starts but windows wont show anything at all, all i see is a black screen.

    Any help?


    13 Jun 13 at 8:31 pm

  22. Dear Jack,

    maybe that could be an VGA driver issue.
    Try to rename the Intel VGA driver.

    Boot from your WIn8 USB Stick / DVD or whatever you have.

    Then open a command prompt like it is described above.

    Do the following steps:

    “cd C:\Windows\System32\Drivers”
    “ren igdkm64.sys igdkm64.sys_”

    Without -> ” <- of course :-)

    Try to reboot :-)


    14 Jun 13 at 4:49 pm

  23. Thanks David for this article. Managed to install Win 8.1 preview in dual boot via EFI, everything seems to work fine so far except the audio drivers. Tried manual install of cirrus drivers, realtek drivers… no luck.


    29 Jun 13 at 3:02 pm

  24. To those that are getting the ‘cannot update boot configuration issue’, the only way I got around it was to use a windows PE environment to set up windows, and manually update the boot configuration. Still had dramas but ended up with a working windows 8 EFI install.
    Followed a method like this url:

    BTW my model is MBP8,2


    4 Jul 13 at 12:40 am

  25. […] pages that helped me create a larger EFI partition first before installing Windows 8 and OS X: – Dual-booting Windows 8 and Mountain Lion natively using EFI – [GUIDE] How To Install Clover 2 Dual-Boot Solution on GA-Z77N-WIFI with Fusion Drive My EFI […]

  26. Actually it is not necessary to “clean”/nuke the mac hard drive with Windows Diskpart as long as it is a pure GPT disk with a protective mbr instead of a “hybrid” mbr. Unfortunately, if you used bootcamp assistant or mac disk utility to create your windows partition, most likely a hybrid mbr will be created and this will only allow installation of windows in BIOS mode. You can convert the disk back to pure GPT (without losing your original partitions) using the GDisk utility available here
    (option “n” in expert options to “create a new protective MBR”).

    Once I confirmed my disk was partitioned as pure GPT with Gdisk, I created the MSR (Microsoft Reserved Partition) and Windows Partition using windows Diskpart.exe and proceeded with Windows 8 installation in efi mode – Mac Mini late 2012, bootcamp 5.0.5033 drivers. Everything seems to work (including Cirrus Audio, Broadcom network wireless, Intel 4000 video and hdmi audio).


    4 Aug 13 at 3:29 am

  27. Hi, thanks for the guide. I’ve been looking for a way to trash the hybrid MBR atrocity. I don’t even like the idea of it, never mind being forced to have one.

    Installation went well on my late 2012 MBP retina 15″ and the system booted fine – for about 12 hours, then it died.
    Is EFI booting Windows 8 64 bit a little fragile?
    When it failed mine reported a “missing operating system”.

    I tried installing again after formatting to GPT and all subsequent installation attempts ended with the failure to update the BCD and installation was terminated by the installer.

    Any suggestions please?

    Mike D

    16 Sep 13 at 10:40 am

  28. Mike, try using gptfdisk as linked in Brendon’s comment. I have used it in the past to repair/modify Apple’s hybrid MBR. Use it to remove the hybrid MBR to return it to just GPT. I suspect that OSX somehow restored the hybrid setup on your machine and that is why you are now getting the “missing operating system” error.


    16 Sep 13 at 1:37 pm

  29. Thanks David, sadly there’s no way to check that now as I’ve re-installed Windows in Boot Camp for the moment due to the “failure to update the boot configuration data” error that I got when trying to re-install it in EFI mode.
    If that were the case what’s to stop OS X from doing the same thing next time, I wonder?

    My most pressing question really is whether EFI booting Windows is a little fragile. Is the boot process easily broken somehow?

    Mike D

    16 Sep 13 at 1:47 pm

  30. For now it does seem to be a bit fragile. If there is any standard MBR data in the protected MBR, Windows will not boot via EFI.


    16 Sep 13 at 2:15 pm

  31. Ok, thanks again David.
    I’ll keep an eye on developments :-)

    Mike D

    16 Sep 13 at 2:17 pm

  32. I haven’t re-installed as yet but I find myself wondering whether my last few attempts (which failed with the “could not update boot configuration data” error) could have been my fault.
    I’m wondering if at the installation stage of Windows I booted the installation media in bios mode rather than EFI. I don’t think I did and I’m usually quite careful when following instructions but I suspect it may cause such an error.
    Presumably in EFI mode Windows would not use a BCD.
    In fact, if that’s what I’ve done, the installation could fail when writing to the MBR to state where the BCD is and as there is no hybrid MBR any more when using GPT it wouldn’t be able to write to it.

    Mike D

    21 Sep 13 at 7:20 am

  33. Nope, I just tried agaoin and definitely booted the cd in efi mode and got the boot configuration error again.

    Mike D

    21 Sep 13 at 9:28 am

  34. So “BCD” stands for “Boot Configuration Data” and is used by both EFI and non-EFI versions of Windows. The BCD store is usually located on the primary partition on non-EFI systems and in the EFI partition for EFI systems.
    I find it strange that your report that the system boots correctly for a period of time before giving you the error.
    Perhaps you can try booting off of your EFI windows install disk and try using the “bootrec /fixboot” command? You may want to simply call “bcdedit /enum all” to get a full output of your current boot configuration to investigate possible issues.
    Hopefully this helps you resolve your issue.


    21 Sep 13 at 11:20 am

  35. Hi again,
    I’ve just wiped my mac’s hard drive again and tried to install Win 8 in efi. 5 times, so far.
    They all fail with the error “failed to update the computer’s boot configuration. Installation cannot continue”
    So it’s not actually Boot Configuration Data, as I previously stated but “computer’s boot configuration”
    I’ve tried running bootrec /fixboot and it reports that the file has been altered by an outside source and cannot be opened,The next installation attempt failed at the same point – ie at the last stage on the original installation screen.
    It copies files, gets them ready for installation, then runs the 3rd and 4th stage and green ticks them all then it fails at the last stage with the above error.

    What I don’t understand is that the HDD is empty apart from a new efi partition, a msr partition and a new primary partition. There’s nothing in any of them so why the “boot configuration” can’t be updated (and updated from what?) I don’t know.

    I even tried bootrec /rebuildBCD which it reports as run ok but still no good.

    On a cleaned disc it’s rather confusing.

    Mike D

    21 Sep 13 at 12:12 pm

  36. I’ve updated the guide to include formatting the EFI partition, this may be related to your problem.


    21 Sep 13 at 12:33 pm

  37. Now that’s very interesting as I was about to go down that route :-)
    Windows is very fussy about its efi partition, apparently.
    I’ll do that now and get back to you after another try, lol.

    Mike D

    21 Sep 13 at 12:36 pm

  38. No good. Same error at the same point.
    It’s all the more galling that my very first attempt at efi installation worked like a charm using your guide.

    Mike D

    21 Sep 13 at 1:41 pm

  39. Hi, I’m now thinking that this is a Microsoft thing and it’s some sort of limit to the number of times you can attempt to install from one install disc. At the last attempt the cd wouldn’t boot at all in efi mode and on occasions didn’t even appear in the boot menu.
    I read a MS article where somebody had the same error (error 0xc000034 BCD error) and the responder (from Microsoft) told the poster not to use a disc which was non-OEM for his hardware. As if it was some sort of check that had been made by the cd, perhaps.
    Anyway I’ll contact MS and see what they say. Mine is a retail disc and has never been used on any hardware other than this Mac. That’s what I bought it for.
    Thanks for your efforts David.

    Mike D

    21 Sep 13 at 4:13 pm

  40. Well I’m up and running! :-)
    It’s been a long road.
    This is on a mid 2012 MacBook Pro retina 15″
    To be honest I’ve used a mixture of your guide and several others in order to get to this stage.
    I’ve made notes and would be happy to post everything I’ve done to get here but that would be a long post. Even longer than your original guide, I suspect.
    Basically the boot configuration problem was worked around with the following:-
    I believe that the fat32 EFI partition must be labelled EFI (with label=EFI after formatting).
    Run the installtion as above and as soon as the message pops up do a hard shutdown. Don’t let the installation roll back!
    Take out the USB/dvd and Alt boot and when the EFI boot for the hard drive shows up plug the USB back in and select EFI boot on the USB.
    At the start screen press shift + f10 for command prompt.
    list volume – NOTE the drive letters of everything
    select volume X – where X is the letter of your fat32 EFI partition
    assign letter=B
    cd /d B:\EFI\Microsoft\Boot\
    ren BCD BCD.bak
    bcdboot C:\Windows /l en-GB /s B: /f ALL – where C is your new Windows installation – en-GB is for UK language, it will normally default to en-US
    Should report boot files written ok.
    wpeutil reboot – taking out the USB and holding Alt to boot

    If it boots you’re good. Mine didn’t and went to a black screen and gave this error “the computer restarted or encountered an unexpected error. Windows installation cannot proceed.

    If that happens don’t panic. DO NOT click on OK
    Hit shift + f10 for command prompt
    navigate to HK Local Machine/SYSTEM/SETUP/STATUS/childcompletion and click (highlight) it
    Look in the right pane and you’ll see setip.exe
    If its value is 1 double-click on setup.exe then change the value to 3
    click OK
    close the window
    close the command prompt
    click on OK in the error window
    Reboot and hope it boots to your shiny new desktop :-)
    At this point I loaded the BootCamp 5 drivers by running the setup.exe
    I then rebooted and suffered a black screen and in an effort to get to the safe mode boot held down the shift key during next boot.
    The system booted to the desktop and I disabled the Intel HD400 driver in Device Manager.
    Rebooted and all was (and still is) fine.

    Mike D

    24 Sep 13 at 12:46 am

  41. Sorry, the “as soon as the message pops up” in line 11 above refers to the “installation could not update boot configuration. Installation can not continue”.

    Also sorry about the length of my last post :-)

    Mike D

    24 Sep 13 at 10:28 am

  42. Thanks for following through and posting your solution! Hopefully it will help someone in the future :)
    Glad you were able to get it working.


    24 Sep 13 at 10:39 am

  43. Alas while a good guide I am getting stuck (Macbook Pro, late 2011) with trying to get Windows 8.1 EFI installed.

    All the attempts (including the helpful BCD and hard reboot advice from Mike D!) end up with it starting to load Windows off the disk and ending up with “Windows could not complete the installation. To install Windows on this computer, restart the installation.”.

    I strongly suspect missing drivers are causing something key to fail. I’ll be trying to build a full 8.1 disk with (give or take) the right drivers sometime perhaps, but otherwise I’m stumped – especially if rebuilding it with drivers fails!


    24 Sep 13 at 1:53 pm

  44. Did it mention that a device wasn’t working at any time?
    In some Macs it seems that it is necessary to delete a video driver (or more than one) from the C:\Windows\System32\Drivers folder (I think it was). Through the command prompt.
    A couple of the known ones are igdkm64.sys and/or igdkmd64.sys.
    Obviously that would depend on your system.
    It might be worth googling on that issue as you will get some hits.

    Mike D

    24 Sep 13 at 2:11 pm

  45. Oh dear, it died again :-(
    I tried to start Windows after a 4 hour(ish) rest and it boots to the black screen with the blue window and stays there. No spinning dots, nothing.
    That’s twice I’ve managed to install it and twice it only lasted about 12 hours before failing.
    This failure was a BCD error again. In fact it was more serious than that as diskpart couldn’t see the EFI partition as a volume. It could list it as a partition but not as a volume.
    Ah well.

    Mike D

    24 Sep 13 at 11:22 pm

  46. Mike, at this point I highly recommend that you use a program like HDTune or Western Digital Lifeguard Diagnostics to check your hard drive as a failing drive could possibly show the symptoms you’ve been describing.


    25 Sep 13 at 12:03 am

  47. Thanks for the suggestion David.
    I’ve just run a Smart Utility long test and the error count is still 0.
    No bad sectors and none pending either.
    It’s a SSD and it’s only 8 or 9 months old (not that it counts for much).
    The “problem” has only showed up with Windows 8 when it’s been installed EFI. No problems at all when running OSX, BootCamp or Ubuntu.
    Though something is obviously amiss somewhere and I do accept your point regarding what’s happened. A failing harddrive would cause this type of problem.
    Watch this space :-)

    Mike D

    25 Sep 13 at 12:25 am

  48. I think it was getting pretty far on the install, it never typically went blank screen oddly! Was 8.1 preview so maybe it fixed some things regarding this. I may try and wit the windows toolkit create an image which removes such display drivers to force the default standard VGA one and see how I go from there :)


    26 Sep 13 at 1:20 am

  49. Well my latest installation of Windows 8 in EFI has now been running for about 36 hours! That’s good :-)
    This one was a pig to get the BCD up and running. I must have tried a dozen times to copy across the boot files and it failed time and time again.
    I restarted the process completely 3 times and then on the last one the files copied across ok. I have no idea what was wrong and all the commands were the same.
    I also disabled the Intel HD4000 device in Windows and I still got BSOD’s due to its driver so I moved the driver (mine was igdkmd64.sys) out of /Windows/System32/Drivers and things have been normal since.
    Anyway it’s working again for the moment :-)

    Mike D

    1 Oct 13 at 9:25 pm

  50. The only difference from previous installs that failed after 12 hours is that since installation I have not run any partitioning tools at all and I have NOT run a Clonezilla image clone of the drive.
    Don’t know if that would make a difference to the time it’s lasted.

    Mike D

    1 Oct 13 at 9:28 pm

  51. Hi Mike, Is your integrated audio working?
    Do you know if the audio works when using the HD4000?
    How’s the battery life using NVIDIA?

    The main reason I would be doing EFI over bootcamp is to get decent battery life, with bootcamp/NVIDIA is pretty poor.


    2 Oct 13 at 1:57 pm

  52. Hi JR, I needed to disable the Intel HD4000 in device manager and also had to remove the igdkmd64.sys driver from the Windows/System32/Drivers folder to get the system to boot. So no the Intel card doesn’t work.
    I believe that sound works throigh the Nvidia driver (from BootCamp support drivers) but only on hdmi output, but have not tested this myself.
    Other than that no, the sound does not work at all and will not as i understand it until Apple can fix something (if they ever do). I suspect that this may happen though as the new MacBook Air supports EFI installation of Windows 8 from INSIDE BootCamp – so that’s progress!
    I disconnected from the mains power whilst running a Windows program outside (on my car) and on disconnection it showed just under 5 hours remaining (with a full battery). After a half hour’s tinkering on the car the battery showed 4 and a half hours left.
    So not OSX type battery life but not too bad really.
    On this installation the fans are much quieter all the time too.

    Mike D

    2 Oct 13 at 9:00 pm

  53. Mike, thanks for your quick and thorough reply.
    I guess I’ll wait until there’s support for the integrated graphics/audio. Also my USB 3 devices are not recognized when using bootcamp, only the USB 2 works.

    Mine with OSX and integrated graphics runs cool and it last several hours, in Windows/Nvidia it gets pretty hot and I can barely get 3 hours out of it.

    Thanks for your comments.


    3 Oct 13 at 6:20 am

  54. An update
    Having run without problem for a week or so I ran a Clonezilla disc image of the EFI partition and the Windows partition.
    This immediately broke the Windows boot, as I suspected it might.
    Windows started to the BSOD screen and offered the option of safe mode, which I chose.
    On getting to the safe mode desktop I opened the Command Prompt and ran diskpart and got to the stage of assigning a letter to the EFI partition (so I could then run the bcd boot command to restore booting).
    Just as the letter was assigned a pop-up window appeared on the desktop. It stated that something was wrong with the EFI partition and that Windows should repair it. I selected OK and after receiving no confirmation of anything having happened I took a chance and restarted.
    Windows booted fine! So there does now appear to be a repair function that works – at least in safe mode.
    I haven’t seen that before.

    Mike D

    9 Oct 13 at 8:38 am

  55. hi all ,

    there is 2 issues no one talk about them :

    1 : no Sound .
    2 : Sleep Doesn’t work .

    Specs : macbook pro 2011 – 2.7GHZ i7 , 8GB Ram – 1ssd & 1 HDD , Hd3000

    So Any Suggestion , Am already tried Many Many solution without no help , all said its about efi firmware update/drivers issue !!!! .

    ahmed kamal

    17 Oct 13 at 6:24 pm

  56. Regarding the disk partitioning part, why do it with Microsoft’s tools since Disk Utility seems to do the same thing for the EFI partition and Windows 8.1 (at least) creates the msr partition if you ask Windows to install to a primary partition.

    This is in regards to a bigger problem of trying to get 8.1 on my new 2013 MacBook Pro which is failing when the installer says “”Failed to create a new system store”.

    Blair Zajac

    16 Nov 13 at 9:16 pm

  57. Disk Utility will create a hybrid mbr when used to create a ms-dos partition.

    Mike D

    17 Nov 13 at 12:53 am

  58. Shift-f10

    this worked for me after the setup failed (error: Setup Could Not Configure Windows on This Computer’s Hardware Error) restart than type the command.

    Duck Man

    19 Nov 13 at 9:00 pm

  59. Has anyone tried this on a latest-gen rMBP?

    The reason I ask is that I’m under the impression that there’s a different version of EFI (more compatible with Win8?) and an updated version of Bootcamp, so I’m trying to figure out whether Bootcamp will install Win8 on an EFI partition, and then boot it without using a BIOS emulation layer?


    28 Nov 13 at 1:32 am

  60. There seems to be some evidence that at least some 2013 MacBook Airs can install Windows 8 via Boot Camp in EFI mode. I have heard nothing about any success with rMBP’s. My 2012 rMBP has had no recent firmware updates or Boot Camp updates and will not install EFI Windows through Boot Camp.
    I do have it installed natively (not through BC) but am having Nvidia driver problems for Windows 8.1.
    As soon as I load a Nvidia driver the monitor drops off :-(

    Mike D

    28 Nov 13 at 4:48 am

  61. I got the whole thing working via this guide and others, on the second drive (ssd) in a 2012 mac mini. But somehow broke the booting. Now the windows partition gives me a ‘no bootable media’ message on a black screen when I start up…..Or sometimes endless spinning dots…. and sometimes the macOS on the disk is recognized, and sometimes not. I’ve used both rEFInd and option to boot, with different and unpredicatable results.

    I have 2 drives, the first has only osx, and it’s slightly corrupted(from mistakenly prepping it for the windows install and recovering with testdisk) but it still boots. OSX says it has no partition table(?) and I should backup and reinstall, which I am planning to do at some point.

    But also I’m wondering if anything about the first drive could affect the second? I’m having trouble keeping rEFInd as my boot manager… it keeps disappearing and I have to re-bless it.

    So I’m wondering if there’s a tool for diagnosing what is going on with the partition table. Is that what gdisk is for? I guess I’ll go read up on that.

    What an odyssey!!!



    8 Dec 13 at 1:30 am

  62. Hello guys,
    I’m trying to install Win 8 Efi on my Macbook Pro retina 15′ (mid 2012 MacBookPro10.1) during the past month but without success.
    I have the same problem as Jack:”I’m stuck at a black screen after first boot attempt, the system starts but windows wont show anything at all, all i see is a black screen.”
    I’ve try to delete the driver file as mentionned but nothing changed.
    I’ve try many time but always “the black screen syndrome”.

    Can someone help me please ?


    15 Dec 13 at 2:50 pm

  63. Which driver are you deleting? There are 2 possible candidates (though you’ll likely only have one installed).
    On the same laptop as you I had igdkmd64.sys and removed that one. This does not seem necessary with Windows 8.1 and there are no BCD errors either.

    Also there’s something else you could try.
    Some people have had success if they hit the enter key on that black screen (I didn’t).
    Also, Windows 8 is set to run automatic repair after 2 unsuccessful boot attempts so what you can do is boot as normal and as soon as you get the blue window screen with the whirling dots (if you get that screen) hold the power button until it shuts down. Then you can do the same thing again.
    Then on the next attempt Windows should run the repair and give you some other options. Choose safe mode from the advanced options.
    Once in safe mode (which uses Microsoft’s basic display driver) you can remove any igdk***64.sys that’s in Windows/System32/Drivers and have a look around to see whether everything looks ok (in device manager, for instance).

    Mike D

    15 Dec 13 at 11:15 pm

  64. Ok thanks for your reply Mike,
    I actually deleted the “igdkmd64.sys” (I just have this one, no others) without any success.
    Hoo, I forgot to say something, I’ve installed Win8 on a usb drive, I hope it comes not from that…


    16 Dec 13 at 1:04 am

  65. Big props to the writer of this guide! This is the only way my mid-2011 MacBook Pro would accept Windows 8.1 EFI mode and Mavericks on my 256GB Samsung 830 SSD.
    I had given many guides a try but none were able to satisfy my macbook.
    FYI, if you have an external hard drive handy, save your OSX install as an image and you can restore it in the step above much faster and no settings lost (for me I just had to log back in to Dropbox). Makes the 10 times I tried to get windows 8.1 on my Mac much easier on your SSD.


    23 Dec 13 at 8:43 pm

  66. Hi folks,

    I am running Windows 8 on my MBpro late 2011 since a while, thanks to this guide. However I am not able to do the update to Windows 8.1. Each method (Appstore, Desktop, Bootstick) fails with an unspecified error.
    Did anyone manage to update? I don’t want to make a complete reinstall..


    28 Dec 13 at 11:42 am

  67. I have an iMac (late 2013) with a fusion drive. I used diskutil to split the fusion drive into SSD and HDD, so I have access to 2 physical disks.

    On my SSD I installed Mavericks. I wanted to use the HDD for Windows and OS X data. So I followed this guide and partitioned my HDD into 500GB for Windows and 2.5TB for Data (HFS+ formatted)

    But Windows 8.1 setup says it can’t find nor create a partition to install on. I used a Windows 8.1 ISO from Microsoft Partner Network and created a USB Bootstick using Bootcamp also containing Drivers.

    Does this only work on the first physical drive? Or I’m missing something else?

    Patrick Heppler

    25 Jan 14 at 6:09 am

  68. Hi to all,

    is sleep working? a saw many post saying that is it not working, (BSOD) after resuming, can someone confirm?

    Ezequiel Block

    31 Jan 14 at 10:39 am

  69. I only get a BSOD on my normal BIOS installation of Windows 8.1 on my Retina MBP when I wake from sleep. I have not witnessed this behavior on any of my other test machines.


    31 Jan 14 at 11:00 am

  70. Thanks David, I has been able to install Windows 8.1, sleep / restore as you said is working, but audio and external monitor (thunderbold) are not, any advise? thanks in advance.

    Ezequiel Block

    31 Jan 14 at 10:58 pm

  71. Hello! has anyone gotten to triple boot windows 8.1, Mavericks, and ubuntu 12.04? I managed to get a full installation on my ssd back when mountain lion, windows 8, and ubuntu share my disk but now i can ever only have 2 os D: I install windows and mac fine booting correctly on both but as soon as i install ubuntu 1) microsoft won’t boot either from the third partition or the msr(which is the one that it usually boots off of) 2) i go back and insert my windows 8 efi dvd and when i try to format and wipe windows 8 partition an error occurs where windows tells me that i do not have a gpt partition on my disk?! and won’t let me install windows 8.1. Please help me/ ps. i tried fixing the bootmrg but when i list volumes efi disappears leading me to believe mac,and ubuntu seem to steal the space away from windows so my next try is to increate efi although i could be totally off :/ pss. I’m on an iMac mid 2010 that i got to triple boot native windows 8, ML, and 12.04 before.

    Gabe Rodriguez

    9 Feb 14 at 12:53 pm

  72. Well Gabe,
    It sounds like you’ve let something (probably OSX) create a hybrid mbr, so the Windows installer sees your drive as a non-gpt disk. This would make it impossible to install Windows via EFI. You can either wipe everything and start from the beginning making sure you don’t convert your gpt to a hybrid mbr or you can try using gptfdisk (as mentioned in a previous comment) to convert your disk to a vanilla gpt configuration… You should also make sure your linux install is configured to boot via EFI before you do that though as converting to pure gpt will render it unbootable otherwise (yes linux geeks, you can fix that, no I don’t really want to go there). Good luck :)


    9 Feb 14 at 2:19 pm

  73. Yes, Thank you! I have wiped everything and installed windows as described by the guide and to test which operating system cause the problem i installed os x on try 1 and ubuntu on try 2 (both after the installation of windows in efi mode). surprisingly os x plays nice with windows’s boot manager however ubuntu does not :/ Installing ubuntu (in the form of Elementary OS X Luna based on 12.04 and running the command to check if it did install it as efi) breaks boot manager and cause windows to be unable to boot. Any help is appreciated :D if we can find a workaround I’m willing to write a guide and make a video walk through!

    Gabe Rodriguez

    9 Feb 14 at 5:44 pm

  74. It’s possible that Elementary cannot install in EFI mode so it’s installing grub to the MBR of the drive. It’s possible that this causes a hybrid MBR to be created, or at least causes Windows to see the MBR and want to boot that way. Of course it can’t because grub is in the MBR where Windows’ boot code would normally be (on a bios system).
    I would suggest checking your disk is still GPT-only and if so try installing Ubuntu 13-10 or something like that which can install in EFI.

    Mike D

    9 Feb 14 at 5:49 pm

  75. I will check right now but i would prefer 12.04 because of the LTS (but at this point I’m willing to give anything a try)

    Gabe Rodriguez

    9 Feb 14 at 5:52 pm

  76. Did you use Bootcamp to install Windows?

    Mike D

    9 Feb 14 at 5:52 pm

  77. There’ll be another Ubuntu LTS out in April if you want to go that way.

    Mike D

    9 Feb 14 at 5:53 pm

  78. No haha i followed this guide except instead of just doing “create partition primary” i allocated space for 3 primary partitions “create partition primary size=79190″ and the last one the former to fully utilize all the space on my drive. So in theory my drive has 5 part ions 0:EFI 1:MSR 2:WINDOWS 3:UBUNTU/MAC 4:MAC/UBUNTU 5or4: RECOVERY HD. I have a vanilla gpt up to the installation of windows and right now I’m checking if i still have a gpt disk after installing linux…

    Gabe Rodriguez

    9 Feb 14 at 5:58 pm

  79. Just checked i lose vanilla gpt after installing linux :/ is there a way to force 12.04 to install via efi? I’m so confused because i checked and efi is echo ed back when i check how linux is installed. Im so perplexed.

    Gabe Rodriguez

    9 Feb 14 at 6:02 pm

  80. Gabe, That sounds correct, I have had issues installing Ubuntu (13 mind you) as EFI. I’ve had to tell it not to install grub during the initial install after making sure that the EFI partition was selected as the EFI partition in the custom disk configuration during install. The trick might be to just not write grub to the drive at all…


    9 Feb 14 at 6:03 pm

  81. If you want to switch back to vanilla gpt after installing ubuntu, gptfdisk has that capability I believe.


    9 Feb 14 at 6:04 pm

  82. That’s a great idea since i end up using a boot manager (refit or refined). Now to look for a way to not install grub at all :/ Can you recommend a way?

    Gabe Rodriguez

    9 Feb 14 at 6:05 pm

  83. or how would you go about making gptfdisk make the disk gpt again?

    Gabe Rodriguez

    9 Feb 14 at 6:07 pm

  84. I haven’t used the Ubuntu 12 installer in a long time, but I believe the 13 installer asks you if you want to install grub to the disk (although that may be just for ubuntu server)
    A quick google search brought this up:


    9 Feb 14 at 6:09 pm

  85. I have just installed Ubuntu 13-10 on my rMBP 10,1 in EFI following (largely) this guide
    As that guide says it’s important to boot from the EFI boot option of the installer AND during installation to make sure that /dev/sda1 (the EFI partition) is mounted as boot/efi

    Installation went fine for me but you also need to make the changes with efibootmgr (as described) or grub won’t show up.

    It’s also vital to check that you have a protective MBR, not a hybrid MBR. gdisk (GPT fdisk) can do that easily (and create a new protective MBR if required).

    Mike D

    9 Feb 14 at 6:10 pm

  86. Sorry David, don’t mean to contradict.

    Mike D

    9 Feb 14 at 6:11 pm

  87. As for gptfdisk:
    From the livecd use apt-get to install it.
    Then from a terminal window use the “sudo gdisk /dev/disk0″ command. (or whatever /dev/disk corresponds to your install)
    “p” will display the partition table to check everything.
    “q” quits if something’s wrong or you’re using the wrong disk.
    “x” gives you the “experts” menu (which is what you want)
    “n” from within the experts menu will reset the gpt back to standard.
    “w” will save the changes.

    Hopefully that works for you :)


    9 Feb 14 at 6:14 pm

  88. wait so if i understand this correctly grub can only be installed on an mbr partition? also Mike when you said “It’s also vital to check that you have a protective MBR, not a hybrid MBR. gdisk (GPT fdisk) can do that easily (and create a new protective MBR if required)” why would i need an MBR? Isn’t the goal to make a disk fully gpt?

    Gabe Rodriguez

    9 Feb 14 at 6:17 pm

  89. To create a new protective MBR fire up gdisk (also known as GPT fdisk) with
    sudo gdisk /dev/disk0 – if you have only one drive

    It’s first few lines of output will tell you whether you have a hybrid MBR or a protective MBR
    To change hybrid to protective you create a new protective MBR as follows

    type x and press enter to get to the expert menu
    then type n and press enter
    then type w and enter to write changes to disk
    Answer y to confirm

    When finished type q to exit gdisk and close terminal.

    Reboot to confirm changes.


    Mike D

    9 Feb 14 at 6:18 pm

  90. Gabe,
    GPT has a “protective mbr” that is placed in the same section of the hard disk that a mbr would normally be. This keeps legacy software from incorrectly thinking that the device is not formatted (and thus potentially damage the partition table). It also makes it so that if something writes to the mbr, the gpt is protected from those changes. That’s why it’s a “protective” mbr.


    9 Feb 14 at 6:20 pm

  91. A GPT-only disk contains a protective MBR as standard.
    And no, grub can be installed in efi mode with later Ubuntu systems which installs it to the Mac’s EFI partition rather than the MBR

    Mike D

    9 Feb 14 at 6:21 pm

  92. Ah ok thank you very much i understand now :) now I’m going to try to install gptfdisk and run it wish me luck :D

    Gabe Rodriguez

    9 Feb 14 at 6:27 pm

  93. David, on a different note, have you seen the latest thoughts on the “cannot update boot configuration data” error on EFI Windows installs?
    It seems that a NVRAM reset cures the problem most of the time.

    Mike D

    9 Feb 14 at 6:28 pm

  94. Mike,
    No I haven’t seen that. Interesting that an NVRAM reset fixes it. Perhaps Apple is caching some of the EFI settings in the NVRAM? I’d be interested to dump the NVRAM on a unit exhibiting that behavior before and after reset and seeing what changes…


    9 Feb 14 at 6:31 pm

  95. David, Lol, find someone with a new rMBP (Haswell) as they’re doing it all the time – through Bootcamp, no less!

    And good luck Gabe :-)

    Mike D

    9 Feb 14 at 6:35 pm

  96. success!!! Thank you mike and David! Windows booted after converting the hybrid gpt to vanilla gpt :D now i will install mac and if that does mess up the boot up managers, as promised, i will write a guide and video tutorial. Again Thank You my friends :D

    Gabe Rodriguez

    9 Feb 14 at 6:37 pm

  97. Excellent! Teamwork, that’s usually best :-)

    Mike D

    9 Feb 14 at 6:39 pm

  98. Great to hear! Hopefully the rest of your install goes without incident :D


    9 Feb 14 at 6:49 pm

  99. Full install without problems I’m using refined but might go back to refit, open to suggestions! I’m in the process of writing a guide. Again Thanks for you help guys!

    Gabe Rodriguez

    9 Feb 14 at 8:20 pm

  100. By the way the command is “sudo /dev/sdletter_of your_drive” (mine was a)

    Gabe Rodriguez

    9 Feb 14 at 8:23 pm

  101. Yes, in Ubuntu it’s /dev/sda for the first drive
    In OSX it’s /dev/disk0

    No need for refined if you followed that guide. Despite what’s said in the guide I’ve got OSX booting through grub, though it’s definitely non-standard :-)

    Mike D

    10 Feb 14 at 1:41 am

  102. An update for Mid 2010 MacBook Pro.
    They (mine at least) still have the problem of “cannot update boot configuration”. I just tried it with Windows 8.1 and ran into the same problem as before, so it doesn’t seem it’s possible on MBs that old.


    12 Feb 14 at 12:56 pm

  103. You could try resetting PRAM/NVRAM as others seem to have had success that way.

    Mike D

    12 Feb 14 at 11:16 pm

  104. Resetting did actually help and I finally managed to boot to Windows using EFI.
    However, once I was in Windows I was plagued with BSODs and random restarts, so I’m back on OSX.

    One thing I noticed during installation that might ease the steps of future, was that partitioning the harddrive was unneccessary.
    I booted straigt to “EFI Boot” and pressed Shift+F10 after selecting the language to start a command prompt.
    From there I started “diskpart” and ran only the following commands:

    select disk 0
    convert gpt

    After exiting diskpart and closing the command prompt I chose a custom installation of Windows (as opposed to the upgrade option). When it asked me which harddrive I wanted it installed on I chose the only one listed, then clicked the “New” button. This then created all the partitions needed.
    So it seems the guide can be simplified a bit.


    13 Feb 14 at 2:52 pm

  105. Glad to hear that the NVRAM reset helped.
    Did the BSOD’s mention an unhandled thread exception or something like that? Or maybe mention the igdkmd64.sys Intel graphics driver?

    Mike D

    13 Feb 14 at 3:10 pm

  106. Yeah, that was one of them.
    I fixed that by deleting the file in question.
    The other problems occured during installation of the Bootcamp-drivers. Some times during the nVidia installation, other times during some other driver. After a couple of those installation crashes/restarts something in Windows probably got corrupted as it refused to start any more.
    I don’t remember the BSODs after this mentioning any files, and it was a different message than the threading one. I want to say the error message included the word “system” but at that point I was pretty tired of the whole thing and had given up.


    13 Feb 14 at 3:15 pm

  107. Thanks for the update,
    The reason that the guide uses a “more complicated” method than you described is because you cannot boot the EFI windows installer on most models (something about the way the hard disk is formatted prevents the windows installer from booting). So the more complex method is described since it works in most cases.
    Also, by manually creating the partitions you have more control over where on the disk (and the size) of the various partitions (super useful if you’re trying to do something unusual).


    13 Feb 14 at 3:16 pm

  108. I have a dual graphics Mac as well and it does cause problems.
    Bootcamp somehow disables the Intel graphics chip but as we’re not using Bootcamp this does not happen.
    As a consequence of this both graphics chips are detected. The Intel driver can cause crashes or black screens on mine.
    Similarly the Nvidia driver causes the PnP screen to drop out, also resulting in a black screen.
    As a result of these issues I’ve disabled both the Intel and Nvidia chips in Device Manager. On rebooting the Microsoft Basic Display driver will load and the system is then usable.
    Obviously gaming wouldn’t be feasible (I wouldn’t imagine) but as I’m not a gamer it’s actually very usable for me.
    Maybe a fix will be found eventually :-)

    (As an aside, the brand new Bootcamp drivers issued today, have the same outcome too – so now fix yet.

    Mike D

    13 Feb 14 at 3:24 pm

  109. Has anyone managed to try this on a Haswell Macbook Pro?

    Thinking of getting a MacBook Pro 15″ top model but without the Nvidia (Iris only) but haven’t found any reports of EFI working.

    Mike S

    17 Feb 14 at 2:59 pm

  110. Some people have installed Windows in Bootcamp on Haswell Mac’s and it actually got installed as EFI. It seems that (at least) some of them don’t create a hybrid MBR when Bootcamp partitions the disk. All kinds of problems are reported during installation such as not being able to install to a GPT disk and, oddly, not being able to install to a MBR disk.
    You really need to know whether Bootcamp created the hybrid MBR after partitioning and before the system restarts. Gdisk can tell you.

    If a hybrid MBR is created you should install in CSM (bios) mode.
    If no hybrid MBR is created (remaining GPT only with a protective MBR) you should install in EFI.

    Obviously you could ignore Bootcamp altogether and install Windows in EFI manually, like most of us have done following this guide.

    Mike D

    17 Feb 14 at 11:36 pm

  111. Thanks Mike.

    I fully intend to do an EFI install but haven’t found many reports of success. This model without NVIDIA should solve some of the problem but I still haven’t found anything about sound drivers working/not working.

    I guess so few people are doing EFI installs that the knowledge pool is shallow.

    Mike S

    19 Feb 14 at 1:49 pm

  112. Mike S, those that have installed in EFI on Haswell’s (whether in Bootcamp or not) have not complained about having no sound, to my knowledge.
    My mid 2012 rMBP (with Nvidia) has no sound in EFI and as both the Intel and Nvidia graphics chips are detected the only answer I found was to disable both and just use the Microsoft Basic driver, which actually works very well. It boots in about 6 seconds too :-)
    But that’s no good if you’re installing Windows for gaming purposes.

    In your position I’d try with Bootcamp first but after the partitioning stage (but before rebooting) I’d run gdisk to confirm whether a hybrid MBR had been created. If not then EFI should be good (but on rebooting I’d also perform a NVRAM reset).

    Mike D

    19 Feb 14 at 1:55 pm

  113. Hi,
    An update.

    Got my rMBP without Nvidia (11,2) and followed your instructions to get Windows 8.1 installed. Upon boot (before bootcamp) only basic graphics display, no network and no sound. After bootcamp drivers 5.1.5640 everything works perfectly. Network started, sound, Intel HD5200 recognised. All good … except having to install 500MB+ of Windows updates ;)


    13 Mar 14 at 10:13 pm

  114. Hey
    works good this tutorials

    only the sound don’t works after install bootcamp drivers.

    Is there a Solution?

    I have MacbookPro 2011 Late 13
    without extra grafikkard. when i install windows via Bootcamp all Works but with EFI native the Sound isn’t working
    The New update gives no New function on Sound Problem

    Solution ?


    21 Mar 14 at 5:14 am

  115. Hey David. Thanks for the awesome walkthrough.

    I’m seeing two issues that I can’t find addressed in your article or the comments. This is on a 13″ Haswell/rMBP

    1) I don’t get an EFI Boot option while option-starting. Only the Windows boot option appears. Tried clearing NVRAM – no change.

    2) If I proceed with the windows-boot option, I get the black screen with blinking cursor, followed by black screen with the win8 logo, I can see the activity light blinking on my USB Win Install drive, then I get a BSOD about the drive having been removed or inaccessible.


    11 Apr 14 at 2:29 am

  116. In my experience I have had limited success when installing (EFI) off of a USB drive… Have you tried a USB Optical drive for the install?
    Also (I haven’t verified this), I have heard that Bootcamp on newer models sometimes does an EFI install when following Apple’s instructions.


    11 Apr 14 at 2:42 am

  117. […] I followed this guide: Dual-booting Windows 8 and Mountain Lion natively using EFI at insideTheAsylum I did this on my late-2013 15" which I configured to have no Nvidia GPU. Everything works and the […]

  118. […] has a power switch easily accessible. I am running Windows 8.1 which I have installed UEFI using this guide. Originally when I received the Sonnet I found out that the PCI slots were only 8x length and so […]

  119. Hello, and thank you for this post. I’ve a slight different situation. I’m trying to install win8.1 onto a clean hard drive for a PC. A dual boot with linux.

    I’ve been having trouble, but your blog has gotten me farthest along, so maybe you could give me more help.

    regarding this point:
    Option-boot the computer when it reboots, but this time choose “EFI Boot” instead of “Windows”

    I think this is MAC specific instructions to reboot but to obtain a list of boot options (eg. disk drive, etc). I don’t have a list of boot options that are titled “EFI boot”. I have other options, none of which include the DVD drive with the installation disk.

    The only UEFI boot option is to boot from the very hard drive that has not yet received windows. So my motherboard appears to be recognizing the new hard drive correctly, but I don’t know how to move past this step, and any suggestions would be very much appreciated.

    For what it’s worth, the mother board I’m using is a gigabyte 990fxa-ud3 and it doesn’t have any options to disable ‘secure-boot’–apparently it’s already compliant or some damn thing.


    4 Jun 14 at 6:42 pm

  120. Great guide. Just to share my experience: Install went fine on a Macbook Pro Mid 2009 (2.53ghz). However, default sound drivers were installed and there was no sound despite the levels fluctuating in the mixer. I guess it had the same problem because of Cyrris audio.

    However, after installing the bootcamp drivers (which worked just fine on non-EFI installs), the restart went into repair mode and I couldn’t get it to boot normally. After 2 days of this nonsense I decided to give up. I’m reinstalling OSX and will just do a normal bootcamp Win 7 (assuming THAT even works.)

    Lucky for me, this system is an old one that my friend gave to me after upgrading, which I just wanted for playing around in OSX. However, from the looks of it, it’s the same bullcrap even on newer systems. Another reason to add to my list to avoid buying Apple products.


    30 Jun 14 at 10:41 am

  121. Hello

    The Option with EFI doesn’t show up for me? any suggestions?



    10 Sep 14 at 1:29 pm

  122. Hello,
    I have a Mac Mini Server mid 2011 with the Intel quad i7.I would like to Install Windows 7 64 on my second drive which is 1 TB (Recently added) and wish to boot with this method but how much do I half to do.

    SN: C07G34JPDJY7

    Keith D

    25 Mar 15 at 5:39 pm

  123. […] + Win8.1 [Vanne] . There it was a EFI installation of Win8.1 rather than a MBR installation. Eg: Dual-booting Windows 8 and Mountain Lion natively using EFI at insideTheAsylum Hello Nando I am getting error code 43 How can I fix this Reply With […]

  124. […] Here is an obviously working setup for Windows 8 (source): […]

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