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MP 1,1-5,1 Installing Windows 10 in Legacy/BIOS mode in cMP with Boot Camp Assistant

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The first post of this thread is a WikiPost and can be edited by anyone with the appropiate permissions. Your edits will be public.
Hi,

I just tried this using the latest version.

I am Running Mojave on a 5,1

I installed Window 10 in Legacy Boot Mode onto a USB/SSD. This worked fine. I then tried to Boot from it and for the PC message "cannot find boot volume, press any key". Is this because it's booting from USB?

It's probably because I need to Restore the EFI? And remembering about a potential problem with about bricking my Mac Pro 5,1. Is it now safe to boot from it without it corrupting my NVRAM?

Once I have the USB/SSD can I then transfer the disk to the internal slot (I can slide the SSB from the box and put it into a sled) and have it boot to windows?

The process was super smooth, really good job guys, thanks a lot!

All the Best
Dave
 
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Hi,

Since doing the above, my OC/Monterey drive no longer boots correct?

When I started the windows install, I removed all drives except for the Mojave, a newly formatted HDD and a formatted ExFAT MBR USB/SSD. It installed ok, I then tried to boot from it (got the message Cannot Find Boot Drive).

I then took the drives out and put back the OC/Monterey drive but it failed to boot. Its boot but just before it will ask me enter log in password, the screen goes black. It looks like it can't set up the RX580 correctly.

I tried Mojave, same result.

I've tried NVRAM deep reset.

Could the Windows install somehow cause my GPU to fail? Or maybe the attempt to boot to windows?

Thanks a lot
Dave
 
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LookToWindward said:
Hi,

I just tried this using the latest version.

I am Running Mojave on a 5,1

I installed Window 10 in Legacy Boot Mode onto a USB/SSD. This worked fine. I then tried to Boot from it and for the PC message "cannot find boot volume, press any key". Is this because it's booting from USB?
Click to expand...
It would be nice to see the log

Screenshot 2024-06-02 at 20.13.15.png


I can boot Windows 10 from USB, but I can’t boot Windows 7, but I don’t have a Mac Pro, I have the PCs in the signature.

LookToWindward said:
It's probably because I need to Restore the EFI? And remembering about a potential problem with about bricking my Mac Pro 5,1. Is it now safe to boot from it without it corrupting my NVRAM?
Click to expand...

The problem may occur if there was a Windows UEFI installation, macschrauber previously wrote about this in this thread.

LookToWindward said:
Once I have the USB/SSD can I then transfer the disk to the internal slot (I can slide the SSB from the box and put it into a sled) and have it boot to windows?
Click to expand...

Yes, if everything was installed correctly)))
 
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Unfortunately the GPU seems to be flaking out - see last message, I have a non-Metal GPU but I suppose that won't work with Windows?

Weirdly, it seems like the DVI port works? I was using the HDMI Port, I also has DP ports but I don't have any DP cables or Monitors
 
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Is the log from the last install still available? I still have the Mojave disk that I didn't the Install from and the USB/SSD. I can do it again and capture the log if need be (given that the GPU holds out!)

I have no more time today, I will start again tomorrow
 
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LookToWindward said:
Hi,

Since doing the above, my OC/Monterey drive no longer boots correct?

When I started the windows install, I removed all drives except for the Mojave, a newly formatted HDD and a formatted ExFAT MBR USB/SSD. It installed ok, I then tried to boot from it (got the message Cannot Find Boot Drive).

I then took the drives out and put back the OC/Monterey drive but it failed to boot. Its boot but just before it will ask me enter log in password, the screen goes black. It looks like it can't set up the RX580 correctly.

I tried Mojave, same result.

I've tried NVRAM deep reset.

Could the Windows install somehow cause my GPU to fail? Or maybe the attempt to boot to windows?

Thanks a lot
Dave
Click to expand...
You are mixing concepts. There are 2 different modes:
Legacy ( MBR or hybrid MBR)
UEFI mode
When you install Windows in Legacy mode you don’t care about the EFI partition as it is not used in this mode. There is no interaction with the NVRAM apart from setting the boot order. In this case deep NVRAM reset should fix any issues providing your chip is OK You may have damaged the NVRAM section with UEFI Windows installl, but not with Legacy.
 
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startergo said:
You are mixing concepts. There are 2 different modes:
Legacy ( MBR or hybrid MBR)
UEFI mode
When you install Windows in Legacy mode you don’t care about the EFI partition as it is not used in this mode. There is no interaction with the NVRAM apart from setting the boot order. In this case deep NVRAM reset should fix any issues providing your chip is OK You may have damaged the NVRAM section with UEFI Windows installl, but not with Legacy.
Click to expand...
Ok, that's what I thought but wanted to confirm
 
Macschrauber said:
I think there is no way to boot a legacy mbr disk from USB on a classic MacPro.

I'd be glad if someone proves me wrong :)
Click to expand...
I will try again and save the logs. If I can't boot from Windows from USB on a Mac Pro 5,1, then I can transfer the SSD from the box to a sled, but it is possible to copy the USB drive to an internal SSD/HDD?
 
LookToWindward said:
I will try again and save the logs. If I can't boot from Windows from USB on a Mac Pro 5,1, then I can transfer the SSD from the box to a sled, but it is possible to copy the USB drive to an internal SSD/HDD?
Click to expand...
You can move the disk physically and plug it in the sata port under the dvd drive, for a quick test. Take care to mount it securely when you leave it there, especially when you move the Mac Pro.

You can use the backup function from Sergey's tool. I used that to copy back an uefi windows disk I have overwritten for a test run.

Would be no big deal if that didnt worked, but I wanted to test that.
 
Windows Install 6.1.7
Mac Pro 5,1
internal HDD, installed in MBR, one Partition exFat 1TB

worked as expected, no extra tools or steps needed

2 Windows Install, Install Windows legacy boot.png
 

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Macschrauber said:
I think there is no way to boot a legacy mbr disk from USB on a classic MacPro.

I'd be glad if someone proves me wrong :)
Click to expand...

With a MacPro5,1, CSM is only available to the 6 southbridge SATA ports.

Some newer Macs with native Thunderbolt ports can do it from USB. Before anyone reads this and then asks it again, adding a Thunderbolt card to a Mac Pro does not magically make CSM available to other ports.
 
@Sergey-Galan I just tried external SSD MBR install and I got the same error as before. This time in Monterey.
 

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So, I compiled hivex from scratch and replaced it in the tools folder. This version looks for the library in /usr/local/lib so I had to copy the library there. This time the Windows on an external drive booted on my MacMini6,2 in MBR mode.
As mentioned earlier cMP can’t boot from an external drive in MBR mode.
 

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startergo said:
@Sergey-Galan I just tried external SSD MBR install and I got the same error as before. This time in Monterey.
Click to expand...
Failed to create main BCD store. But this time the hivexsh utility worked, but stopped without finishing its work. I don’t know what prevented it. In version 6.1.8 added a check for BCD creation.

Screenshot 2024-06-23 at 00.58.21.png
 

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  • Windows Install.zip
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Hi,


I've looked at the posts from last night and not sure what to do now.

What is the index field and how does it relate to the drive you are using? I've looked back and can't see it mentioned anywhere. I'm guessing that it refers to the list of index that are displayed when you D+D the ISO file?

It defaults to index 10, which is "Windows 10 Pro for Workstations" in this case?

What I'd really like from this is Windows on an Internal HDD (I have a 2 TB I can use for testing). Is it possible to install straight onto this?

I saw a post about using the optical bay, this machine has 2 DVD drives in the Optical bays, I can remove a drive from it or I have an additional Optical bay (from a broken 4,1) with 1 DVD drive in it, I could maybe swap the optical bays, but I'm confused as to why I would do this, is it because it will try to boot first from the DVDs?

-----------

New Install:

I have a Mojave boot disk, in Bay 1 and a 480 GB USB/SSD. No other HDD/SSDs in system.

The USB/SSD drive is not partitioned, it has just been formatted as one ExFAT/MBR drive.

I tried again and this saved the log - attached. I now have a USB/SSD with windows 10 Installed.

I can now move this SSD from the USB Box and put it into a sled and try to boot or I can try to put it in the optical bay or something else?

All the Best
Dave
 

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Ok, I took the SSD out of the box and put it into a sled.

The Sled is in Bay 1 and no other drives connected.

It started to boot then I got and error "Recovery, your PC/Device needs to be repaired"

BootBCD, Error code 24

At least it attempted to boot!

I'm happy to try it again, is there a new version? I'm currently using version 6.1.7
 
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LookToWindward said:
Ok, I took the SSD out of the box and put it into a sled.

The Sled is in Bay 1 and no other drives connected.

It started to boot then I got and error "Recovery, your PC/Device needs to be repaired"

BootBCD, Error code 24

At least it attempted to boot!

I'm happy to try it again, is there a new version? I'm currently using version 6.1.7
Click to expand...
I have just installed in Monterey Windows on an external single MBR drive with a partition formatted in exFAT, installed it in the second SATA in the DVD bay and booted in cMP. Everything works as designed.
 
If you had a previous installation of the application you need to uninstall it with something like App Cleaner Uninstaller or similar before installing a new version.
 
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