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Guide: Multibooting UEFI on Separate Drives

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Shut down, disconnect the drive.
I already have Windows and macOS installed on separate SSDs on an existing installation and everything is running smooth. I already have a 3rd SSD in the same tower I'd like to install a Linux distro on. Since everything is all buttoned up and to save me a little time, is it necessary to disconnect the Windows SSD before proceeding with the Linux installation?
 

Going Bald

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I already have Windows and macOS installed on separate SSDs on an existing installation and everything is running smooth. I already have a 3rd SSD in the same tower I'd like to install a Linux distro on. Since everything is all buttoned up and to save me a little time, is it necessary to disconnect the Windows SSD before proceeding with the Linux installation?
No. As long as you are able to distinguish which drive is which there is no need. Disconnecting the other drives is a precaution to prevent mistakenly overwriting one OS over another. With the newer UEFI of most new boards you can bot to UEFI and simply disable the ports, eliminating the need to physically disconnect the drives (provided you can determine which drive is on which port).
 
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Should not be. The only difference when you installed using bootcamp is that is placed the UEFI partition at the beginning of the drive. Windows usually installs the UEFI either second or third position and Clover does not like it there. You should have no problems.
Okay, cool. Well I ended up reformatting the whole drive and installing Windows as if it were all I had. Dual booting by choosing at BIOS right now. Might work to integrate it into clover soon but I'm not stressing it.

That being said, if that Bootcamp EFI was still there, I understand it won't hurt anything but what effect does it have by just sitting there?
 

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Okay, cool. Well I ended up reformatting the whole drive and installing Windows as if it were all I had. Dual booting by choosing at BIOS right now. Might work to integrate it into clover soon but I'm not stressing it.

That being said, if that Bootcamp EFI was still there, I understand it won't hurt anything but what effect does it have by just sitting there?
None. If the bootcamp EFI were still there the Win10 installer would have used it for the boot files. One way to check - open the Win10 disk management app and examine the drive structure. If the EFI partition of 200MB is the first partition shown, then the bootcamp created EFI is still there. If there is a larger partition labeled RETools, and the EFI partition is the 3rd shown, then Win10 installer wiped the drive and created its own partitions.
 
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Hey guys, I'm running my build successfully and happily :)
I'm running into an issue now, that hopefully someone here might've been through it already.

I'm reading a lot of articles on how to dual boot on separate drives and how it should be the easiest thing on earth... that's why I'm posting here...

I've got my macOS running on UEFI Clover, but I can not install windows on a separate drive at all!

I've created a bootable drive using RUFUS and selecting the UEFI option, I'm able to boot windows installer and reach the drives screen, but can't get past it. It either tells me windows can't format the drive or if I manually format it using diskpart.exe it tells me it can't prepare windows to boot.

Has anyone installed windows on Clover using UEFI with an already installed macOS? How?

EDIT: Pictures with both errors added.

408431


408432


Thanks!
 
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Going Bald

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Hey guys, I'm running my build successfully and happily :)
I'm running into an issue now, that hopefully someone here might've been through it already.

I'm reading a lot of articles on how to dual boot on separate drives and how it should be the easiest thing on earth... that's why I'm posting here...

I've got my macOS running on UEFI Clover, but I can not install windows on a separate drive at all!

I've created a bootable drive using RUFUS and selecting the UEFI option, I'm able to boot windows installer and reach the drives screen, but can't get past it. It either tells me windows can't format the drive or if I manually format it using diskpart.exe it tells me it can't prepare windows to boot.

Has anyone installed windows on Clover using UEFI with an already installed macOS? How?

EDIT: Pictures with both errors added.

View attachment 408431

View attachment 408432

Thanks!
The first pic is from a drive which previously had Windows installed on it from the look of the partitions. From the bottom up, select a partition and delete it until you have only unallocated free space and the 200MB EFI partition left.
Boot Mac OS, mount the EFI partition and delete all files in the partition. Boot to UEFI and disable the Mac OS drive SATA port so Win10 installer cannot install files on the Mac drive.
Boot the Win10 installer and select the unallocated section of the drive for the installation of Win10 and hit enter - Win10 installer should format and create its own partitioning scheme and install from there.
 
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The first pic is from a drive which previously had Windows installed on it from the look of the partitions. From the bottom up, select a partition and delete it until you have only unallocated free space and the 200MB EFI partition left.
Boot Mac OS, mount the EFI partition and delete all files in the partition. Boot to UEFI and disable the Mac OS drive SATA port so Win10 installer cannot install files on the Mac drive.
Boot the Win10 installer and select the unallocated section of the drive for the installation of Win10 and hit enter - Win10 installer should format and create its own partitioning scheme and install from there.
Thanks for your answer.

From the bottom up, select a partition and delete it until you have only unallocated free space and the 200MB EFI partition left.
I did this quite a few times.

Boot to UEFI and disable the Mac OS drive SATA port so Win10 installer cannot install files on the Mac drive.
I'm sorry, but what do you mean by "boot to UEFI"? Boot to clover and, if so, from there disable my macOS drive? Manually disconnect my macOS drive? If the latter, is that a must? because my macOS drive is NVME...

Boot the Win10 installer and select the unallocated section of the drive for the installation of Win10 and hit enter - Win10 installer should format and create its own partitioning scheme and install from there.
As for this final part, it's pretty clear, it's actually what I've been doing so far.


Could you please clarify those points for me?

Thanks again
 

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Thanks for your answer.


I did this quite a few times.


I'm sorry, but what do you mean by "boot to UEFI"? Boot to clover and, if so, from there disable my macOS drive? Manually disconnect my macOS drive? If the latter, is that a must? because my macOS drive is NVME...


As for this final part, it's pretty clear, it's actually what I've been doing so far.


Could you please clarify those points for me?

Thanks again
Boot to UEFI = Boot to BIOS.
In BIOS / UEFI there should be a section showing all drives connected. There should be an option to disable the drive ports, even if NVME
 
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Boot to UEFI = Boot to BIOS.
In BIOS / UEFI there should be a section showing all drives connected. There should be an option to disable the drive ports, even if NVME
Thank you, but it didn't work. I got the same error. I'm going to detail as much as possible, to see if you can help me spot the error...

  1. Created the USB using RUFUS and selected GPT
  2. Erased the drive using Disk Utility and choosing MacOS Extended (journaled) and GUID Partition Map
  3. Boot to USB
  4. On Windows installer, erase every partition, but the EFI
  5. Click on Install
  6. Error...
Here are some pictures showing my BIOS configuration:

408591


408592


408593


I still get the same error about not being able to prepare to boot. The only thing I didn't do was to physically remove my NVMe drive. If you tell me that might help, I can try, though.

Thanks for your help.
 
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Going Bald

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