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whg

macrumors regular
Original poster
Aug 2, 2012
236
153
Switzerland
I don't know if something similar has already been posted. I'm aware that Windows cannot reboot into macOS when installed on an APFS partition. Could the following be a solution to this problem? I saw this tip in the German c't magazine 23/2017 page 131:

Download the High Sierra Installer from the Apple store, cancel the installation, open a terminal window and enter

/App*/Inst*High*/C*/R*/startosinstall --converttoapfs NO

Did someone already test this and can confirm that this would be a viable solution to the Bootcamp issue. I have a Mac Pro 5,1 with Sierra and Windows in a Bootcamp partition on an SSD drive. I plan to use a graphics card that doesn't support a boot screen. Switching back to macOS would be difficult. I would also like being able to access the Mac partition from Windows with my Paragon HFS+ driver.
 
You can boot back using the Startup Manager. Hold down Option key when starting up your Mac and select your Macintosh HD. New drivers are needed for windows.
 
Paragon HFS+ may not work in the latest Windows 10.

If you just want a switchable solution.

Disable SIP + Bootchamp

work flawlessly in latest High Sierra and Windows 10.

I am using this combination right now with a non flashed PC GPU.
 
You can boot back using the Startup Manager. Hold down Option key when starting up your Mac and select your Macintosh HD. New drivers are needed for windows.

Note the user pointing out that they think not supporting the boot screen is a good idea.
 
This tip is already all over the Internet and I have seen multiple people claiming success, including on this forum. I have not tried it myself, and apple my change or disable the function of the option at any time.
 
This tip is already all over the Internet and I have seen multiple people claiming success, including on this forum. I have not tried it myself, and apple my change or disable the function of the option at any time.

The option boot is there for many many years, not for this AFPS issue. I don’t think Apple will change that. It’s a very use tool in some cases, and really nothing hurt to stay there. Also so believe it’s a part of the firmware, not the OS (because this option boot works even no HDD inside the Mac). I really don’t think Apple would like mod this part of the firmware for no apparent reason. I’m fact, this long available option boot safe them this time.

As a Mac Pro 5,1 user, I used all factory default GPU, Apple approved GPU, normal PC GPU with native MacOS support, and even my current 1080Ti which is a non Apple supported GPU. And I use MacOS, Windows, Linux... we really need to know well how to deal with this kind of issue.

In fact, the Apple native start up manager is slow and lack of function (but it works under this situation). On the other hand, rEFInd (or even Cover) can do a much better job.

Another simple way to go back to MacOS is by performing a PRAM reset. After a PRAM reset, the machine will always boot back to MacOS regardless of start up management available to the user or not.
 
The option boot is there for many many years, not for this AFPS issue. I don’t think Apple will change that.

It’s not about the boot process, but to make an upgrade install with this option: “--converttoapfs NO”
This is new with High Sierra and could very well be disabled by Apple at some point.

If I understand the original poster correct, he is using a mac with a gfx card without EFI ROM and thus no drivers to display the boot screen, which makes it harder to navigate it.
 
It’s not about the boot process, but to make an upgrade install with this option: “--converttoapfs NO”
This is new with High Sierra and could very well be disabled by Apple at some point.

If I understand the original poster correct, he is using a mac with a gfx card without EFI ROM and thus no drivers to display the boot screen, which makes it harder to navigate it.

I see, yes, that option may gone at anytime.

That’s my understanding as well. He is now using a non Mac EFI card, which has no bootscteen. In fact, AFAIK, using the startup manager blindly is not quite possible, we don’t even know if it’s there. Despite some users claim that’s they can select blindly, but more said no matter what they pressed, nothing will show up. Not booting into any partiton.

At this moment, there is a project on going in the Mac Pro forum about using rEFInd to load the graphic card’s UEFI GOP, therefore, even the PC non Mac EFI GPU can show the “boot screen”. At least one user on another forum claim that him made it already. But may need a bit more time to confirm it’s doable for everyone.
 
It’s not about the boot process, but to make an upgrade install with this option: “--converttoapfs NO”
This is new with High Sierra and could very well be disabled by Apple at some point.

If I understand the original poster correct, he is using a mac with a gfx card without EFI ROM and thus no drivers to display the boot screen, which makes it harder to navigate it.
Thanks to everyone who replied to my question. So, do you think that Apple would convert my HFS+ partition to APFS with a future upgrade without asking the user? Or do you just say that this option may not exist in future installers?

I'm still not really sure if booting into macOS High Sierra will be possible from Bootcamp Windows 10 (without going through the Alt and boot screen option or using Bootchamp)?

I could just do the experiment, but if it fails I would have to reinstall and re-activate Windows again which would probable require a call to Microsoft (or 2 if I want to use the Windows Bootcamp partition also through a Parallels VM).
 
Thanks to everyone who replied to my question. So, do you think that Apple would convert my HFS+ partition to APFS with a future upgrade without asking the user? Or do you just say that this option may not exist in future installers?

I'm still not really sure if booting into macOS High Sierra will be possible from Bootcamp Windows 10 (without going through the Alt and boot screen option or using Bootchamp)?

I could just do the experiment, but if it fails I would have to reinstall and re-activate Windows again which would probable require a call to Microsoft (or 2 if I want to use the Windows Bootcamp partition also through a Parallels VM).

WinClone can save your entire Bootcamp partiton to a image file. If anything goes south, it’s much easier to recovery from an image backup, no need to reinstall anything or re-activate anything.

And IMO, yes, Apple highly likely will convert some HFS+ partiton into APFS without acknowledge / asking the user in future. So, even you can stay (or going back) to HFS+, you may suddenly realise your partiton is conveyed to APFS after a minor OS update. Very Apple style.

At this moment, NO, there is no direct method to boot back to High Sierra APFS partiton in bootcamp. And no one know when will Apple provide the bootcamp driver. TBH, at this stage, even the MacOS driver barely work. Their Windows APFS driver may be not even reach the alpha stage.
 
Or do you just say that this option may not exist in future installers?
How Apple plans is hard to predict, but as their support document indicates that HFS+ is not seen as an option, I would prepare for that.

Now for your case I think the problem you have might be intermittent as I am sure Apple will at some point release some kind of APFS support for Bootcamp/Windows.
 
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