Restart in OS X from Windows 10

Discussion in 'Mac Pro' started by Neanderphil, Dec 5, 2015.

  1. Neanderphil macrumors member


    Sep 28, 2006

    I'm currently using a non-efi card in my Mac Pro (see sig). When in Windows 10 I'm unable to use the bootcamp assistant to boot back into OS X (El Capitan). Using this option brings me back into Windows 10.

    I currently work round this by performing a PRAM reset to get back into OS X. Anyone aware of why this may be happening and what I can do to fix it? Thanks ;)
  2. SoyCapitanSoyCapitan macrumors 68040


    Jul 4, 2015
    You mean Boot Camp Control Panel? It should work fine if you did a default install with no mods. There is an app you can use called Bootchamp for booting to Windows and back to OSX by default, but the latest version no longer works on El Capitan without disabling SIP. There is an older version of Bootchamp that does still work but read the comments at developers site for more details.
  3. Neanderphil thread starter macrumors member


    Sep 28, 2006
    Thanks for the reply. I had tried the older version of Bootcamp, 1.5.3, but no luck with that either. Might try disabling SIP, but need to get out my old 4870 for recovery mode. o_O Was hoping to find a lazy solution. :oops:
  4. Mejenborg macrumors newbie


    Apr 22, 2016
    Aarhus, Denmark
    I'm having the exact same problem - have you found a workaround?
  5. jonen560ti macrumors member


    Dec 29, 2015
    hold down alt as the mac boots and pick your osx partition from the boot menu. not a fix per say, but a good alternative
  6. h9826790 macrumors G4


    Apr 3, 2014
    Hong Kong
    OP is using a non EFI GPU at this moment. That's why he can't use this work around.

    To OP, did you choose "restart to OSX" option from the tray icon, or actually open the bootcamp apps in Windows, and choose the OS X partition, then restart your Mac?
  7. b.lam macrumors newbie

    Sep 5, 2010
    I had the same issue after installing El Capitan and Windows 10. As it turns out, you have to disable SIP. If enabled, it will also prohibit that Windows can set the boot partition via the Bootcamp tools.
  8. throAU macrumors 601


    Feb 13, 2012
    Perth, Western Australia
    Makes sense. Otherwise any Windows malware could modify the boot loader to subvert OS X.
  9. SoyCapitanSoyCapitan, May 8, 2016
    Last edited: May 8, 2016

    SoyCapitanSoyCapitan macrumors 68040


    Jul 4, 2015
    Would be very hard to do in Windows 10 as many sources of malware and unsigned software would run in virtual environments that are sandboxed from the system itself. The hardware would be even harder to get to.
  10. Synchro3, May 8, 2016
    Last edited: May 8, 2016

    Synchro3 macrumors 68000


    Jan 12, 2014
    1. Straight forward: Shut down, disconnect the Windows drive physically, power on, Mac Pro will search the next bootable volume *, could take a while. Once OS X booted, define OS X as start volume again.

    * If that doesn't work, reset PRAM.

    2. Buy an EFI card. A Mac Pro without Option boot etc is not recommended. With an EFI card you will have PCI-E 2.0 speed in Windows too.
  11. owbp macrumors 6502a


    Jan 28, 2016
    Belgrade, Serbia
    As noted, if your OS X HDD is in the first slot the PRAM reset on the reboot should do the trick.

    But, i have 10.11 with SIP enabled and i can use, without any problems, Restart in OS X option i Bootcamp.
    I installed fresh Windows10 on HDD, then installed Bootcamp drivers for Win7 and then installed drivers from this topic, Bootcamp 6 support, to reenable volume screen "icon" with similar screen candy and Bootcamp app.
  12. haralds macrumors 6502a


    Jan 3, 2014
    Silicon Valley, CA
    It looks like a bug, I have the same issue with a standard BootCamp install on a separate drive. I use Option-Boot. BTW, I have a similar issues that selecting Yosemite or Lion boot partitions from El Cap does not work until after I have option booted into the other partitions.
  13. Mejenborg macrumors newbie


    Apr 22, 2016
    Aarhus, Denmark
    When installing windows 10, did you have the OSX disk present in the system as well, or did you take it out before booting the windows installer? Or maybe OS X and Windows is on the same disk?

    Also did you remove the OS X Boot Camp Assistant created BOOTCAMP partition, and made the windows installer make its own partitions?
  14. owbp macrumors 6502a


    Jan 28, 2016
    Belgrade, Serbia
    That is the only thing I'm not 100% sure about, but i think that I've let Bootcamp Assistant format the whole disk.
    Diskutil is showing that AFAIK
    Screen Shot 2016-05-09 at 03.26.13.png

    I had really bad experience letting Windows do anything with disks in Mac.

    I formatted HDD in Bootcamp Assistant and removed HDD from Mac.
    Started installation in PC (old&cheap Dell Optiplex 755), only formatting BOOTCAMP partition in installer, not erasing or anything else.
    On the first Win10 Installation reboot i've shut down PC, put HDD in Mac as only disk and booted up.
    Installation did continue and everything went fine. At the end, you know it from previous post, i installed Bootcamp Drivers for Win7 and then Drivers from the link for Win 10.

    The only problems i have with this Windows installation is:
    - can't let it sleep (won't wake up, but i have to troubleshoot is it the GPU or hibernate mode on Win)
    - and every time i restart to Windows i have to replug mouse in different USB on my Apple Pro Keyboard.
    If i just reboot from Win to Win, or boot into it after being shut down, mouse works from login screen.

    P.S. Ive upgraded from Win7 to 10 few times, it being the only OS on HDD or on its own partition (same disk with OS X), but this is the only time I've done fresh Windows 10 installation and that is the method i used.
  15. Hugebricks, Nov 29, 2016
    Last edited: Nov 30, 2016

    Hugebricks macrumors newbie


    Nov 29, 2016
    Hey everyone, sorry to bump an old thread but I'm having a similar problem and can't seem to find a solution. Here's what I've tried so far:

    1. Mac Pro 4.1 -> 5.1 with GTX 970 PC (non-flashed). Originally had Yosemite on one HDD, Windows 7 on another HDD.
    2. No issues using Startup Disk to restart into Windows 7, and no issues using bootcamp to restart in Yosemite.
    3. Upgraded to Sierra.
    4. Using startup in Sierra to reboot in Windows 7 works, but bootcamp in Windows 7 is unable to reboot into Sierra, and the computer will only boot in Windows 7.
    5. I have gotten around this by using a Windows 7 install disc and holding down C upon startup. Bootcamp was then able to restart in Sierra. I would guess it worked because this method doesn't change Sierra's startup disk option, but I was only able to do it once and don't want to rely on it if possible.
    6. I have a GT120 for boot screens, but Windows 7 will only output video through the GT120 when the 970 is also present, and it's not preferable to keep swapping video cards.
    6. I tried using a separate install of Yosemite as a sort of startup disk selector, but going from Sierra to Yosemite to Windows 7 results in only being able to reboot in Windows 7 or Yosemite.
    7. I did install Clover after reading this thread and following the advice: and was able to successfully boot with it on the GT120 through holding option at startup then choosing Clover, but if I switched over to the 970 the screen would remain black, so I've since reverted to a backup to remove Clover.
    8. I tried disabling SIP to see if that would allow bootcamp in Windows 7 to restart in Sierra, but nothing changed; once Sierra is told to boot in another OS, I can't get back to Sierra without boot screens.
    9. Holding X upon startup doesn't work either.
    10. I've tried resetting the NVRAM before and after installing, then removing Clover, but the above still happens.
    11. SMC reset same as above.

    So at this point I need some hand holding:

    A: Do I need to do a fresh install of Windows 7 with a specific formatting on the disk through bootcamp, etc?
    B: Is the Windows 7 version of bootcamp just absolutely unable to play nice with Sierra?
    C: Does anyone know the exact steps needed to make Clover show boot screens on a Mac Pro with an Nvidia PC card?

    I really feel like I'm missing something with Clover especially when others have claimed success: and I've tried to research it as much as possible, but I'm not sure where I'm going wrong.

    Any help or advice would be greatly appreciated.


    After trying Clover again with a fresh install of Sierra, and trying every configuration that seemed relevant to my untrained eyes, I couldn't manage to get a boot screen on my 970. I did however, give BootChamp a shot since I already had SIP disabled. While it didn't work right away, re-disabling SIP did make it work. I can now use BootChamp to get to Windows 7, and BootCamp will successfully restart in Sierra.
  16. fendersrule, Jun 26, 2017
    Last edited: Jun 26, 2017

    fendersrule macrumors 6502

    Oct 9, 2008
    Same problem here. There's got to be a work around. If you're using a non-flashed card, then prepare to suffer by this ailment.

    Seems like there should be some app, or something in Windows 10 that will allow you to select a boot disk. There's nothing!

    In MacOS Sierra, selecting your Windows 10 disk in Startup Disk will restart the computer and will be at a command line that says something like "boot disk not found".

    In MacOS, Bootchamp errors and whines about some **** when you try to restart into windows.

    In Windows 10 EFI, selecting "Restart into Mac OS X" from boot camp just reboots into windows.

    The only thing you can do is boot back into MacOS Sierra using the command + P + R option. That's a guaranteed boot into MacOS.

    I haven't found a way to boot back into Windows 10 yet, other than pulling my MacOS drive out, which sucks because it's on a PCI-E card. Not realistic to do that.

    This cannot be rocket surgery. And even with the nVidia web drivers coming out and with GTX cards becoming popular on the Mac Pro, you'd think people would have found a way to swap back and forth in Windows 10 EFI and MacOS Sierra!
  17. SoyCapitanSoyCapitan macrumors 68040


    Jul 4, 2015
    Why isn't your Apple Boot Camp app not installed on Windows?
  18. fendersrule, Jun 26, 2017
    Last edited: Jun 27, 2017

    fendersrule macrumors 6502

    Oct 9, 2008
    It is. That's why I wrote this:

    In Windows 10 EFI, selecting "Restart into Mac OS X" from boot camp just reboots into windows.

    I thought this was a known issue.

    There seems to be no way to reboot back into MacOS from Windows 10 EFI unless you command + P + R it when using a non-flashed GPU.

    So far, there is no way to boot back into Windows 10 EFI that I can find, unless you physically disconnect stuff when using a non-flashed GPU.

    I didn't use bootcamp assistant. I followed a process and natively installed it on a separate drive.
  19. goMac macrumors 603

    Apr 15, 2004
    Windows has a startup disk selector in the Boot Camp control panel (NOT the Restart into Mac OS X shortcut.) Give that a try.

    I haven't tried it with EFI Windows. But it works just fine in non-EFI Windows.
  20. fendersrule macrumors 6502

    Oct 9, 2008
    Hmm. Is that in the "Bootcamp control panel"?

    There is hardly anything there on an EFI Version of windows. Certainly no "Start up" Tab.

    That's probably why it doesn't work.

    Either A) I need to reinstall bootcamp, or B) It's like that because of SIP.
  21. iamtheonlyone4ever Suspended


    May 27, 2016
    is not a software problem is a hardware problem
    simply get a new card it doesn't have to be a very expensive one
    get a cheap one as long as it has EUFI support
    or buy an use one

    if that will be a hackintosh then you simply be force to use a legacy bootloader
    you won't be able to use clover in EUFI mode because the card doesn't support EUFI

    well the same thing in a mac
    you need a card that support EUFI
    you can't change to legacy bios on a mac
    the way we do in a hackintosh
  22. fendersrule macrumors 6502

    Oct 9, 2008
    I have bootcamp 4.0 installed. It does not have the the "startup disk" tab. Is there another version I can installed? I tried to install the newer one, and it said "Not supported" and the installer quit. Ugh.

    with SIP disabled, bootchamp WORKS.

    I just need to figure out how to get back into MacOS from here!
  23. fendersrule macrumors 6502

    Oct 9, 2008
    Downloading bootcamp 5.1.5621 fixed it. Make sure to open the command prompt as admin and point it to the .msi setup file that's inside one of the folders. It will install. That's the one you need for a Mac Pro 5,1.

    With that, you get the startup disk panel for Bootcamp.

    I'm now able to boot to and from Windows and Mac OS.

    It's actually easier to do it this way rather than holding the alt key. Much faster.

    So-long boot screens!

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