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How to select OC boot disk from within Windows 10?

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I recently switched from an Apple magic keyboard plugged in by USB to K380 bluetooth, and can no longer select my boot disk from the opencore boot menu.


When in macOS and wanting to switch to Windows, it's easy.  I simply pick the Windows drive from the Start Disk menu in System Preferences.  But once I'm in Windows and reboot, I just keep returning to Windows.


Can either of these two scenarios be accomplished:

-Make OC only boot to Windows once on reboot, then return to macOS as the default?  That way when I'm done with Windows and reboot, I return to macOS.

-Somehow select the macOS boot drive from inside Windows 10?


Either of these would solve my problem.



Edited by douirc
  • douirc changed the title to How to select OC boot disk from within Windows 10?

Sounds like you want to setup OpenCore to:

  1. boot your macOS disk/partition by default
  2. manually select the Windows disk/partition in OC Picker to boot Win10

This can be achieved through NVRAM so you must make sure that you have that working whether natively or through emulation. Last time I checked, this was done by setting Misc->Security->AllowSetDefaultto true in your OC config and you could then set your default partition through [CTRL][Index] or [CTRL][ENTER].


Check latest arrangement in the OpenCore manual available here.


Afaik, there's no such thing as "selecting macOS boot drive from inside Windows 10" to reboot into macOS from Windows. I'm pretty sure that only your bootloader can do that because Windows only offers a boot menu when several Windows installations co-exist on a same drive/system but have a look at this if you want to experiment.

thanks for the reply.  not sure I was clear enough in my request.


opencore bootloader shows all my boot options no problem and I can pick which OS I want to boot, macOS or Windows.  It always defaults to my last choice, as it should, which means NVRAM is working.  the problem is, since I've switched to a BT keyboard, I can no longer make a selection during boot because EUFI doesn't see the BT keyboard.  as a result, whichever OS I booted last is the automatic pick every time I reboot. 


so, getting from macOS -> Windows is easy enough using Startup Disk in System Preferences, but going from Windows -> macOS is currently impossible.


Is there a way for NVRAM NOT to remember the last OS selected?  can opencore be forced to an OS on every reboot, regardless of the last OS selected?  this could maybe solve my problem.

If it's only a problem of Logitech Bluetooth K380 keyboard not working at BIOS level and/or in OC Picker before the OS boots, check if your BT module supports HID proxy mode (and set if appropriate). HID proxy works perfectly on my old 2007 Dell Vostro 200 desktop and its original Dell BT keyboard and mouse (and the dedicated BT USB dongle) so I'd be very surprised if that did not work on much more modern hardware.



Have a USB keyboard plugged to prevent any OS booting up by entering BIOS settings or displaying the boot menu. If applicable, press the pairing button on the BT module, then press the pairing button on keyboard and mouse. If HID proxy mode is supported, both devices should then work from the moment the PC is switched on as if they were wired USB models. Of course, I don't expect this to be possible with a built-in/internal card-based BT module only initialised at OS startup and that does not offer physical/manual pairing facility. So, it just depends on what BT module you have/use for that BT keyboard.

It is possible to use the boot camp tools to select which OS to boot, assuming you are booting Windows through OpenCore. I'm not sure if it's possible to select though if not booting through OpenCore.
This is an example from my Ryzen Desktop

This does not need to be a bootcamp installation, it just involves using brigadier to download the boot camp tools within windows, and then installing them. You can remove a lot of the drivers from it as well if you don't need them:

@douircYou could Set PickerAttributes to 17 as a workaround. It enables the  Mouse Cursor in BootPicker if your Keyboard is not working. Have you tried any of the Keyboard Drivers included in the Drivers Folder yet?

  • 1 month later...
Posted (edited)

Wow!  By accident I was clicking the arrows on the BT keyboard instead of the wired keyboard at the opencore boot menu and the BT keyboard worked!  It took a second for the BT keyboard to connect, but once connected I was able to select my boot options and continue loading.  So nice I don't need the wired keyboard anymore.


btw, I have the K380 + Fenvi FV-T919.  Maybe that's why? Does Fenvi have plans to release a 5.0 version that's OOTB compatible with macOS?

Edited by douirc
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