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Never use Clover on a real Mac, you will brick your BootROM. Clover interferes with the NVRAM, causing havoc.
Yes I read about that, a lot of people zapped it. There is at least one coder who did it successfully, but i was not recommending ito be used directly. This was only to Abdyfranco as an idea to his development.
 
OK, I read this whole thread.

Am I reasoning this right:

- Now in 10.13.6 and 10.14 the sure bet is to use Apple Script with manual setup of drive ID (via diskutil list info) and that should work in all cases,
- The precondition is to turn-off SIP, but that has to be done in Recovery mode,
- If you are running non-boot-screen card (like me with RX 580) you have to do it blindly in CMD+R+S Single mode?
- SIP is re-enabling itself after PRAM reset (which is needed to reboot in Mac as BootCamp in Win can't do that now?).

I am missing something? Not a very happy situation for anyone with a modern non-Apple card. :(
 
Almost right.

If you intall Windows 10 on a diffrent HD, in Legacy mode (DVD), BootChamp will work in Mojave (10.14). Even script will work with "bless", and "-next only". BUT not entirely in EFI mode. I have see post here saying that it worked but not for me. It is working to that extend that One can boot from OSX to Windows 10 (EFI). My script looked like;

sudo bless -device /dev/disk5s2 -mount /Volumes/No NAME -setBoot -nextonly

Where "NO NAME" is my EFI partition in my "EFI" installation. NOT my BOOTCAMP partition.

But then you have to shut down, pull the HD out and reboot to be able to get back to OSX. SIP will not be enable if you pull the HD out. Othwise you will be stuck in a "Windows boot-loop". No way I found my way back from EFI to OSX. So not fully functional.

Best regards

/Per


OK, I read this whole thread.

Am I reasoning this right:

- Now in 10.13.6 and 10.14 the sure bet is to use Apple Script with manual setup of drive ID (via diskutil list info) and that should work in all cases,
- The precondition is to turn-off SIP, but that has to be done in Recovery mode,
- If you are running non-boot-screen card (like me with RX 580) you have to do it blindly in CMD+R+S Single mode?
- SIP is re-enabling itself after PRAM reset (which is needed to reboot in Mac as BootCamp in Win can't do that now?).

I am missing something? Not a very happy situation for anyone with a modern non-Apple card. :(
 
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OK, I read this whole thread.

Am I reasoning this right:

- Now in 10.13.6 and 10.14 the sure bet is to use Apple Script with manual setup of drive ID (via diskutil list info) and that should work in all cases,
- The precondition is to turn-off SIP, but that has to be done in Recovery mode,
- If you are running non-boot-screen card (like me with RX 580) you have to do it blindly in CMD+R+S Single mode?
- SIP is re-enabling itself after PRAM reset (which is needed to reboot in Mac as BootCamp in Win can't do that now?).

I am missing something? Not a very happy situation for anyone with a modern non-Apple card. :(
Let me see if I can remember everything :)

I like using scripts to boot into Windows or other Mac OS's, which I can customize and access from the Menubar. But there are several other programs you can use that have some disadvantages like not storing your password. However, which script to use for Windows depends on whether you are booting Windows in the Legacy BIOS mode (you probably are if you used Bootcamp Assistant) or in the UEFI mode (which requires you to install Windows by booting the Windows installer in the UEFI mode). If you aren't sure you can check while running Windows (Google for how).

------

For the UEFI mode you can use this script, or modify as needed, which will automatically determine your drive ID each time it is used (because it can change from boot to boot):

# My Win 10 EFI booting requires -device /dev/diskXs1 be included in the "bless" command.
# This script solves the problem of the Disk ID assigned to the Win 10 physical disk changing
# from one power-up to another. The Disk ID depends on when it is enumerated during boot.

# change BOOTCAMP to your Win 10 volume name, and substitute your password for "your_password".

set Win_devID to do shell script "diskutil info BOOTCAMP | grep Node"
# this assigns the string "Device Node: /dev/diskXsY" to the Win_devID variable, where X is unpredictable

set Win_devID to (text -7 thru -2 of Win_devID) & "1"
# This strips everything except "diskXs" and appends a "1" for the EFI location (which is always "1")

display dialog "Windows 10 EFI Volume was assigned as " & Win_devID buttons {"Cancel", "Boot Win10"}

do shell script "bless -device \"/dev/" & Win_devID & "\" -mount /Volumes/EFI -setBoot -nextonly" password "your_password" with administrator privileges

tell application "Finder" to restart

-------

You can use this script for Windows Legacy-BIOS Boot:

# change BOOTCAMP to your Win 10 volume name, and substitute your password for "your_password".

display dialog
"Windows 10 Legacy-BIOS Boot" buttons {"Cancel", "Boot Win10"}

do shell script "bless -mount /Volumes/BOOTCAMP -setBoot -nextonly -legacy" password "your_password" with administrator privileges

tell application "Finder" to restart

-------

You can use this script to boot into another Mac OS (sub in the name of your Mac OS disc in place of "Mojave"):

display dialog "Boot to MacOS Volume Mojave" buttons {"Cancel", "Save", "Once"}

set choice to the button returned of the result as text

if (choice) = "Once" then
do shell script "bless -mount /Volumes/\"Mojave\" -setBoot -nextonly" password "your_password" with administrator privileges

else if (choice) = "Save" then
do shell script "bless -mount /Volumes/\"Mojave\" -setBoot" password "your_password" with administrator privileges

end if

tell application "Finder" to restart

-------


Even though you are running a video card without boot screens it will still provide you with video screens for the Recovery mode (Command-R at startup - takes a while so be patience holding the keys down). Then using the terminal type:

csrutil enable --without nvram

And yes, if you ever do a PRAM reset, you will have to disable the SIP nvram again.



[doublepost=1539512155][/doublepost]
But then you have to shut down, pull the HD out and reboot to be able to get back to OSX. SIP will not be enable if you pull the HD out. Othwise you will be stuck in a "Windows boot-loop". No way I found my way back from EFI to OSX. So not fully functional.
That's because you updated Windows to the latest version. Stick with v1803 for now and you won't have that problem.
 
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OK, I read this whole thread.

Am I reasoning this right:

- Now in 10.13.6 and 10.14 the sure bet is to use Apple Script with manual setup of drive ID (via diskutil list info) and that should work in all cases,
- The precondition is to turn-off SIP, but that has to be done in Recovery mode,
- If you are running non-boot-screen card (like me with RX 580) you have to do it blindly in CMD+R+S Single mode?
- SIP is re-enabling itself after PRAM reset (which is needed to reboot in Mac as BootCamp in Win can't do that now?).

I am missing something? Not a very happy situation for anyone with a modern non-Apple card. :(

RX580 can access normal recovery partiton. You can try, if you hold Command + R during boot, as long as the recovery partition is there. You will able to see it and use it.
 
I agree with h9826790. Done it myself. You can access Recovery partition with Sapphire RX 580 8G, Mojave.

I will challenge You PianoPro :):);)

I have an old Win10 1709 build. I do a clean EFI install and see how it goes.

Best regards

/Per
 
I agree with h9826790. Done it myself. You can access Recovery partition with Sapphire RX 580 8G, Mojave.

I will challenge You PianoPro :):);)

I have an old Win10 1709 build. I do a clean EFI install and see how it goes.

Best regards

/Per
I had Win10 1709. No problem. Updated to 1803, no problem. Update to 1809 and stuck in Windows. It's a well known problem. Look at other threads.
 
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I challenged you PianoPro, and lost!:):D

Can now boot into EFI mode and back via Terminal. Thank you for the last piece in my EFI puzzle:). No more 1809 for now (don't know how I missed that??).

Best regards

/Per
 
Followup re abdyfranco's Boot Manager (1.0)

HW flashed Mac 5,1
Physical drives
Bay 1: 2TB APFS SSD macOS HS 10.13.6, primary bootvol
Bay 2: 500gb NTFS Win7, problematic bootvol, Boot Camp install
Bay 3: 2TB HD GUID macOS 10.13.6, mirrored bootable backup of primary bootvol
Bay 4: 500gb HD reserve, MacOS Extended Journaled

Unflashed GTX960 for GPU.

Prior situation (recap, this is the familiar issue most of us are having):
Using Boot Camp, Win 7 vol is assignable as bootvol from HS. Once booted into Win 7, APFS vol is invisible to Win Boot Camp. Win Boot Camp thinks it can see and bless Bay 3 backup but to date I have not been able to get it to successfully do so. I don't recall if I have tried to boot directly to the HD backup from the SSD HS install, will do so in a moment. Resolution to stuck-in-Win7 reboots was swapping in OEM video card and using boot screen volume selection procedure.

First crack at using Boot Manager: app runs, IDs volumes appropriately, looks promising. Legacy mode on. Attempt at rebooting into Windows produces restart in HS from SSD in Bay 1.

Second shot: Legacy mode off. Reboots to HS from SSD Bay 1.

Third shot: tried booting into bootable backup volume, no go, same result.

UPDATE: successfully booted into backup volume and then back to HS SSD after using Startup Disk both ways.

Then I tried booting into the Win 7 vol from the HS backup volume, selecting Win 7 bootvol from macOS Startup Disk Preferences pane... and I'm stuck in windows again. Will continue tomfoolery in new post.
 
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Have the guys at Paragon managed to do something then?
I've downloaded and will install, when I have time to mess about.

£44 is a bit steep but if it has some kind of magic drivers that enable BC to see and boot from APFS volumes.......
 
So, to boot into Windows when you get the No bootable device message, the best way it.......?
 
So, to boot into Windows when you get the No bootable device message, the best way it.......?

PianoPro in message #154 explains the scripts you can use. But if you have Windows installed in EFI mode it should be reinstalled in Legacy mode to prevent corruption of the firmware.
 
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MisterAndrew, can you link to the bricking report from your front-page sticky? I have been following this thread along and don't recall seeing it. Also, you seem to have removed some of your original instructional material, I think, but the editing feature doesn't allow access to revisions. Is that correct?
 
MisterAndrew, can you link to the bricking report from your front-page sticky? I have been following this thread along and don't recall seeing it. Also, you seem to have removed some of your original instructional material, I think, but the editing feature doesn't allow access to revisions. Is that correct?

Yes, the information about the firmware corruption due to the signing of Secure Boot certificates is detailed in this thread: https://forums.macrumors.com/thread...-140-0-0-0-0-has-native-nvme-support.2132317/

I deleted the instructions because they were for EFI mode. Windows should be installed in Legacy mode.
 
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PianoPro in message #154 explains the scripts you can use. But if you have Windows installed in EFI mode it should be reinstalled in Legacy mode to prevent corruption of the firmware.
Ok, this sounds quite involved. I need to do some reading. Thanks.
 
Yes, the information about the firmware corruption due to the signing of Secure Boot certificates is detailed in this thread: https://forums.macrumors.com/thread...-140-0-0-0-0-has-native-nvme-support.2132317/

I deleted the instructions because they were for EFI mode. Windows should be installed in Legacy mode.

Was there ever any actual advantage to installing in EFI mode on the cMP? I know for years there have been lots of posts here with people trying to get EFI mode to work for Win7, 8 and 10. But taking the risks aside, what's the benefit?

Edit: what I'm seeing on a google search is support for "Fast Boot" which shaves a couple of seconds off of the boot time. But does the cMP's EFI 1.10 even support "Fast Boot" or was that only part of UEFI?
 
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... following up from Win7 boot loop

cmd-opt-p-r successfully booted to Bay 1 SSD HS 10.13.6 but without Nvidia web driver loading. Used Screen Sharing to access boot session and select driver, rebooted into HS 10.13.6 again without Nvidia driver. Accessed via Screen Sharing (and a remote Terminal session to poke around a bit). Double-checked selected startup disk as displayed in System Preferences > Startup Disk, none was shown as selected, explicitly selected Bay 1 SSD 10.13.6, re-set Nvidia web driver as reboot video driver using Nvidia Driver Manager drop down, rebooted into 10.13.6 with expected Nvidia driver active.

I guess I won't push on with getting Win7 to behave until I have a better grasp on MisterAndrew's concerns re firmware corruption.
[doublepost=1539803680][/doublepost]
Yes, the information about the firmware corruption due to the signing of Secure Boot certificates is detailed in this thread: https://forums.macrumors.com/thread...-140-0-0-0-0-has-native-nvme-support.2132317/

I deleted the instructions because they were for EFI mode. Windows should be installed in Legacy mode.

Thanks for clarifying. I'm guessing I don't have to worry about this since I am using Win 7. When I ran diskutil the NTFS volume does not show an EFI partition.

My next series of experiments was intended to be monkeying with PianoPro's scripts. PianoPro, is that a sensible course of action?
 
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Question, is there a way to see what windows install type you have without booting into it, you know finding a particular file while searching the hard drive with Finder?

Just had a look at my Windows disk and wondering if I do in fact need to reinstall. Can anybody offer any advice before I go any further pls, (FDisk Partition Scheme seems odd?);
#: TYPE NAME SIZE IDENTIFIER
0: FDisk_partition_scheme *512.1 GB disk2
1: Windows_NTFS NATIVE81 511.2 GB disk2s1
2: 0x27 471.9 MB disk2s2

Device Identifier: disk2
Device Node: /dev/disk2
Whole: Yes
Part of Whole: disk2
Device / Media Name: S3
Volume Name: Not applicable (no file system)
Mounted: Not applicable (no file system)
File System: None
Content (IOContent): FDisk_partition_scheme
OS Can Be Installed: No
Media Type: Generic
Protocol: USB
SMART Status: Not Supported
Disk Size: 512.1 GB (512110190592 Bytes) (exactly 1000215216 512-Byte-Units)
Device Block Size: 512 Bytes
Read-Only Media: No
Read-Only Volume: Not applicable (no file system)
Device Location: External
Removable Media: Fixed
Virtual: No

Just as an aside for those wanting know their install type without actually booting into Windows. I believe if you peruse the C drive and follow, ..\windows\panther\setupact.log, look for a line with the text, Callback_BootEnvironmentDetect, that will tell you.
 
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Question, is there a way to see what windows install type you have without booting into it, you know finding a particular file while searching the hard drive with Finder?

Just had a look at my Windows disk and wondering if I do in fact need to reinstall. Can anybody offer any advice before I go any further pls, (FDisk Partition Scheme seems odd?);
#: TYPE NAME SIZE IDENTIFIER
0: FDisk_partition_scheme *512.1 GB disk2
1: Windows_NTFS NATIVE81 511.2 GB disk2s1
2: 0x27 471.9 MB disk2s2

Device Identifier: disk2
Device Node: /dev/disk2
Whole: Yes
Part of Whole: disk2
Device / Media Name: S3
Volume Name: Not applicable (no file system)
Mounted: Not applicable (no file system)
File System: None
Content (IOContent): FDisk_partition_scheme
OS Can Be Installed: No
Media Type: Generic
Protocol: USB
SMART Status: Not Supported
Disk Size: 512.1 GB (512110190592 Bytes) (exactly 1000215216 512-Byte-Units)
Device Block Size: 512 Bytes
Read-Only Media: No
Read-Only Volume: Not applicable (no file system)
Device Location: External
Removable Media: Fixed
Virtual: No

Just as an aside for those wanting know their install type without actually booting into Windows. I believe if you peruse the C drive and follow, ..\windows\panther\setupact.log, look for a line with the text, Callback_BootEnvironmentDetect, that will tell you.

Yeah, if there is an EFI folder in the root of the Windows drive then it's installed in UEFI mode.

https://docs.microsoft.com/en-us/wi...desktop/boot-to-uefi-mode-or-legacy-bios-mode
[doublepost=1540029505][/doublepost]I just reinstalled Windows 10 in Legacy mode. I formatted the drive with MBR partition scheme in exFAT. I downloaded an ISO of the October 2018 update (version 1809) and burned it to a DVD. My Mac Pro wouldn't boot from it though. So I booted a Windows 7 DVD and installed that first. Then I made sure there was no EFI folder in the root of the Windows drive so it was installed in Legacy mode. Then I installed Windows 10. Then I installed the Boot Camp 5 drivers for the Mac Pro 5,1 and then I installed the Boot Camp 6.1 drivers for the iMac Pro which I obtained using the Brigadier app. The iMac Pro Boot Camp installer gives an error preventing installation, but there's a workaround here: https://jeffw.net/2015/09/08/this-v...s-not-intended-for-this-computer-model-fixed/

When I installed Windows I took out my Mac drives and now that I've reinstalled them I able to boot back into Windows from the Startup Disk system preferences pane in Mojave. The Boot Camp control panel in Windows shows the APFS Mac drives, but it just labels them as "Mac." I selected one and I lucked out selecting my main macOS install. So Apple has fixed it in the latest release! No need to use any of these fancy tricks now unless you want to and you can keep SIP fully enabled.

https://github.com/timsutton/brigadier
 
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Yeah, if there is an EFI folder in the root of the Windows drive then it's installed in UEFI mode.

https://docs.microsoft.com/en-us/wi...desktop/boot-to-uefi-mode-or-legacy-bios-mode
[doublepost=1540029505][/doublepost]I just reinstalled Windows 10 in Legacy mode. I formatted the drive with MBR partition scheme in exFAT. I downloaded an ISO of the October 2018 update (version 1809) and burned it to a DVD. My Mac Pro wouldn't boot from it though. So I booted a Windows 7 DVD and installed that first. Then I made sure there was no EFI folder in the root of the Windows drive so it was installed in Legacy mode. Then I installed Windows 10. Then I installed the Boot Camp 5 drivers for the Mac Pro 5,1 and then I installed the Boot Camp 6.1 drivers for the iMac Pro which I obtained using the Brigadier app. The iMac Pro Boot Camp installer gives an error preventing installation, but there's a workaround here: https://jeffw.net/2015/09/08/this-v...s-not-intended-for-this-computer-model-fixed/

When I installed Windows I took out my Mac drives and now that I've reinstalled them I able to boot back into Windows from the Startup Disk system preferences pane in Mojave. The Boot Camp control panel in Windows shows the APFS Mac drives, but it just labels them as "Mac." I selected one and I lucked out selecting my main macOS install. So Apple has fixed it in the latest release! No need to use any of these fancy tricks now unless you want to and you can keep SIP fully enabled.

https://github.com/timsutton/brigadier

Thanks for this great news. Will do exactly the same thing later.
 
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Yeah, if there is an EFI folder in the root of the Windows drive then it's installed in UEFI mode.

https://docs.microsoft.com/en-us/wi...desktop/boot-to-uefi-mode-or-legacy-bios-mode
[doublepost=1540029505][/doublepost]I just reinstalled Windows 10 in Legacy mode. I formatted the drive with MBR partition scheme in exFAT. I downloaded an ISO of the October 2018 update (version 1809) and burned it to a DVD. My Mac Pro wouldn't boot from it though. So I booted a Windows 7 DVD and installed that first. Then I made sure there was no EFI folder in the root of the Windows drive so it was installed in Legacy mode. Then I installed Windows 10. Then I installed the Boot Camp 5 drivers for the Mac Pro 5,1 and then I installed the Boot Camp 6.1 drivers for the iMac Pro which I obtained using the Brigadier app. The iMac Pro Boot Camp installer gives an error preventing installation, but there's a workaround here: https://jeffw.net/2015/09/08/this-v...s-not-intended-for-this-computer-model-fixed/

When I installed Windows I took out my Mac drives and now that I've reinstalled them I able to boot back into Windows from the Startup Disk system preferences pane in Mojave. The Boot Camp control panel in Windows shows the APFS Mac drives, but it just labels them as "Mac." I selected one and I lucked out selecting my main macOS install. So Apple has fixed it in the latest release! No need to use any of these fancy tricks now unless you want to and you can keep SIP fully enabled.

https://github.com/timsutton/brigadier
Thanks, valuable info there. Gonna give all that a shot too. Hopefully tonight.
Then I'll use the tool linked here to sort my personal effects.
https://support.microsoft.com/en-us...-easy-transfer-is-not-available-in-windows-10

EDIT - That's annoying. The free offer has gone.
 
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How did you download BootCamp 6? WHen I use Brigadier.exe it downloads BootCamp 031 from 2011??

/Per


Yeah, if there is an EFI folder in the root of the Windows drive then it's installed in UEFI mode.

https://docs.microsoft.com/en-us/wi...desktop/boot-to-uefi-mode-or-legacy-bios-mode
[doublepost=1540029505][/doublepost]I just reinstalled Windows 10 in Legacy mode. I formatted the drive with MBR partition scheme in exFAT. I downloaded an ISO of the October 2018 update (version 1809) and burned it to a DVD. My Mac Pro wouldn't boot from it though. So I booted a Windows 7 DVD and installed that first. Then I made sure there was no EFI folder in the root of the Windows drive so it was installed in Legacy mode. Then I installed Windows 10. Then I installed the Boot Camp 5 drivers for the Mac Pro 5,1 and then I installed the Boot Camp 6.1 drivers for the iMac Pro which I obtained using the Brigadier app. The iMac Pro Boot Camp installer gives an error preventing installation, but there's a workaround here: https://jeffw.net/2015/09/08/this-v...s-not-intended-for-this-computer-model-fixed/

When I installed Windows I took out my Mac drives and now that I've reinstalled them I able to boot back into Windows from the Startup Disk system preferences pane in Mojave. The Boot Camp control panel in Windows shows the APFS Mac drives, but it just labels them as "Mac." I selected one and I lucked out selecting my main macOS install. So Apple has fixed it in the latest release! No need to use any of these fancy tricks now unless you want to and you can keep SIP fully enabled.

https://github.com/timsutton/brigadier
 
Yeah, if there is an EFI folder in the root of the Windows drive then it's installed in UEFI mode.

https://docs.microsoft.com/en-us/wi...desktop/boot-to-uefi-mode-or-legacy-bios-mode
[doublepost=1540029505][/doublepost]I just reinstalled Windows 10 in Legacy mode. I formatted the drive with MBR partition scheme in exFAT. I downloaded an ISO of the October 2018 update (version 1809) and burned it to a DVD. My Mac Pro wouldn't boot from it though. So I booted a Windows 7 DVD and installed that first. Then I made sure there was no EFI folder in the root of the Windows drive so it was installed in Legacy mode. Then I installed Windows 10. Then I installed the Boot Camp 5 drivers for the Mac Pro 5,1 and then I installed the Boot Camp 6.1 drivers for the iMac Pro which I obtained using the Brigadier app. The iMac Pro Boot Camp installer gives an error preventing installation, but there's a workaround here: https://jeffw.net/2015/09/08/this-v...s-not-intended-for-this-computer-model-fixed/

When I installed Windows I took out my Mac drives and now that I've reinstalled them I able to boot back into Windows from the Startup Disk system preferences pane in Mojave. The Boot Camp control panel in Windows shows the APFS Mac drives, but it just labels them as "Mac." I selected one and I lucked out selecting my main macOS install. So Apple has fixed it in the latest release! No need to use any of these fancy tricks now unless you want to and you can keep SIP fully enabled.

https://github.com/timsutton/brigadier

Awesome! Thanks for detailing all the steps. I wonder if there's an easier way to get Win10 installed in legacy mode than having to deal with installing Win7 first. I think EFI mode can be effectively removed from an installer by deleting the root EFI folder from the installer drive. Are we required to boot from a DVD to install in legacy mode or can a USB installer be used instead? If DVD is required then I suppose the ISO file can be edited to remove the EFI folder before it is burned.

I'll try to play around with some of this next week unless someone beats me to it. Would be nice to figure out the easiest surefire method.

And yet at the same time I also wonder if EFI mode isn't truly a problem either. I think tsialex said the only cases he's seen with multiple certificates in NVRAM were people who had installed the ill-fated 0087 bootrom. I never installed 0087 on mine (0084>0085>0089>138 and will go to 140 when 10.14.1 is released) so I may still try EFI mode and then dump my ROM again to see if multiple certificates exist.
 
Yeah, if there is an EFI folder in the root of the Windows drive then it's installed in UEFI mode.

https://docs.microsoft.com/en-us/wi...desktop/boot-to-uefi-mode-or-legacy-bios-mode
[doublepost=1540029505][/doublepost]I just reinstalled Windows 10 in Legacy mode. I formatted the drive with MBR partition scheme in exFAT. I downloaded an ISO of the October 2018 update (version 1809) and burned it to a DVD. My Mac Pro wouldn't boot from it though. So I booted a Windows 7 DVD and installed that first. Then I made sure there was no EFI folder in the root of the Windows drive so it was installed in Legacy mode. Then I installed Windows 10. Then I installed the Boot Camp 5 drivers for the Mac Pro 5,1 and then I installed the Boot Camp 6.1 drivers for the iMac Pro which I obtained using the Brigadier app. The iMac Pro Boot Camp installer gives an error preventing installation, but there's a workaround here: https://jeffw.net/2015/09/08/this-v...s-not-intended-for-this-computer-model-fixed/

When I installed Windows I took out my Mac drives and now that I've reinstalled them I able to boot back into Windows from the Startup Disk system preferences pane in Mojave. The Boot Camp control panel in Windows shows the APFS Mac drives, but it just labels them as "Mac." I selected one and I lucked out selecting my main macOS install. So Apple has fixed it in the latest release! No need to use any of these fancy tricks now unless you want to and you can keep SIP fully enabled.

https://github.com/timsutton/brigadier
As far as I know, from installing windows in CSM/Legacy mode, AHCI is disabled and IDE is instead used which halves the speeds of the already slow Sata II ports unless you convert your Windows installation to EFI by using mbr2gpt or installing Windows in EFI mode.

That's the drawback of running Windows in legacy mode on the cMP
 
Ah OK. I vaguely remember this now. I think there's a method to force AHCI mode though, which is discussed in this thread. Anyone wanting to try it should read through the whole thread as it appears it breaks Sleep mode and there are some other tips posted by others (none of which I have tried).

I'm leaning back towards just using EFI mode, and binwalking my bootrom periodically to see if any multiple certificates show up.
 
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