Boot Manager: A Boot Screen Alternative in the status bar of your Mac.

[K.J.]

this is the "boot hook" by Open Core, if you dont want it then set LauncherOption in OpenCore to Disabled.

this is this boot001 ... line in the dumper as it is sometimes hard to get it away, so I added a line if that boot hook is in the nvram variables.

This is a nice and wanted feature to survive nvram resets and to set OpenCore's default selection by the startvolume prefpane.


About the old Bootblock:
The Bootblock never gets updated by regular Firmware Updates. My theory why is to let a failsafe in the firmware chip to load the firmware rescue cd if something fails.

tbh the firmware rescue cd never worked for me. Firmware rescue is in my experience taking out the flash chip and replace it with a new flashed one with firmware and personal machine's IDs.

The only way to get the bootblock updated is by manual firmware reconstruction.

tsialex and me are afaik the two guys what can do that job. I owe my first steps into firmware investigation to him and he is my mentor ;-)

Thx for details.
TSIALEX I know from before solutions about HW and he is TOP.
For my complication, now I just for safe over VinClone done backup of my WinDisk and NOW I dont see any of my 2 Windows drives. Its frustrated that when no change was made in setups and installations jut missed visibility under macOS (Win Boot Drive).
But my question is still same - please do you have any way how to do ability from macOS Monterey (MP5.1 unsupported with OCLP) to reboot ONLY ONCE to Windows and after reboot or shutdown again boot into macOS (?)
Due APFS problem Windows OS not sees in BootCamp panel bootdrive macOS OCLP Monterey.
Due "SDErrorDomain error 104" is unable to manually choose Windows drive to boot natively from macOS OCLP Monterey.
Due "BootBlock" in unable to reboot into different native supported macOS from macOS OCLP Monterey. Stillrebooting in macOs Monterey OCLP.

My thniking was to put in between another macOS native supported ro reboot into it where are not new locking/blocking features from AppleOS and in it to reboot into Windows. After that in Windows will be visible this native macOS for reboot again back into it without NVRAM reset and then to choose to reboot in OCLP macOS Monterey back. I know its 2step/4step stolution but I thank that it can work.
But now I see only another additioning problems and complication.

THE BEST option for silution is to implement "something as BLESS command" but 100% working in Monterey as ability for users to use old working command BLESS (once and permanet), that was perfectly suitable before thoose "security disabilities from Apple"...
And additionally ADD GOP INIT for all possible GPUs without bootscreen wich will solve 99% booting issues in this kind of way...

 

[K.J.]

or maybe some additional manipulation on EFI partition to ADD "Microsoft booter" ...

 

[Macschrauber]

for best understanding and guidiance read the 1st wiki post of the OpenCore Thread

OpenCore on the Mac Pro

This guide explains how to use the excellent OpenCore boot loader to install, run, and update the latest version of macOS on the MacPro5,1, resulting in a clean, unaltered operating system just like on a supported Mac.

forums.macrumors.com

Key words to look for is LauncherOption, RequestBootVarRouting and of course the windows part.

The latest OpenCore implements a way to run the native boot selector from the OpenCore menu. This happened just a few days before. This can be the solution for booting what OC can't do.

 

[K.J.]

or maybe some additional manipulation on EFI partition to ADD "Microsoft booter" ...

for best understanding and guidiance read the 1st wiki post of the OpenCore Thread

OpenCore on the Mac Pro

This guide explains how to use the excellent OpenCore boot loader to install, run, and update the latest version of macOS on the MacPro5,1, resulting in a clean, unaltered operating system just like on a supported Mac.

forums.macrumors.com

Key words to look for is LauncherOption, RequestBootVarRouting and of course the windows part.

The latest OpenCore implements a way to run the native boot selector from the OpenCore menu. This happened just a few days before. This can be the solution for booting what OC can't do.

Thx ... sure OCLP is the best option to smoothly and pseudonatively run macOS on unsupported MAC.
But actual need is to have user-friendly and safe DUALBOOTING between OCLP macOS + Windows and that is what Iam finding a way...
Sure Iam doing actually another try-ways to be sure what will go and what not.

 

[K.J.]

to Macschrauber
Please can you provide to me FULL Folder/Files LIST in your EFI partition with OCLP in MacPro5.1.
Iam trying anything to get back to see any of my WindowsOS drive in OCLP macOS Monetery SystemPrefs BootDrivePicker ...
Clonned macOS drive is visible and sure older before OCLP Monterey bootable macOS 10.11.6 too but no Windows as GUID and as MBR. MBR was before visible too vithout problems and bootable. BOTH are 100% working and bootable TESTED (only withou nonpresent OCLP macOS disk). All have own dedicated drive so they are not in partition.

My actual EFI list is attached.
Thank you.
K.J.

 

[K.J.]

... wich AMD card(s) have working Apple bootscreen in MacPro5.1 (prebooting environment posting from MP7.1 wich is not my case) ... just thinking about absolute change GPU - but its totaly new/brand new unused fresh ... unable to use it anywhere.
Secondary add is that if I have present Apple GT120 original official Apple nVidia TOGEHTER with AMD RX 5500 XT my MacPro5.1 stuck in booting or not boot ... jut to need to get rid of one of them...
It is "secondary/another" possible solution to get BootScreen on GT120 just for Windows boot and for macOS use AMD.
Sure -1 PCI port wich is problematic due ventilation or use to another gadgets/HW

and after all Iam thinking to use eGPU without restrictions for MacPro to use beasts as RTX4080 for rendering/working due I have ThunderBolt in PCIe for that prepared ... and sure for AppleCinemaDisplay 27" over TB