Can't install Windows 10 UEFI next to MacOS High Sierra on same SSD

[uchika96]

Hi everyone,
I have tried over and over again to install Windows 10 on the same SSD (the only one I have on my laptop) but I always get the same error.
The procedure I have followed is this one.
1)I have installed MacOS with Clover UEFI after setting the BIOS:

• LEGACY SUPPORT
• UEFI first
• Disable fast boot
• Disable secure boot

2)I partitioned the drive with:

• MacOS (already installed) -> APFS
• Windows10 -> MacOS Extended Journaled (about 60gb)

3)I have booted into Windows 10 EFI from boot menu using both a USB 2 and 3 port.
ALTERNATIVE 1
4)I have deleted Windows10 partition and created a new one
5)I get this error when selecting the primary partition created:
"We couldn't create a new partition or locate an existing one. For more information, see the Setup log files"
ALTERNATIVE 2
4)I have deleted Windows 10 partition and hit next
5)I get this error:
"Windows could not prepare the computer to boot into the next phase of installtion. To install Windows, restart the installation"

I will attach 2 photos I have taken of the errors.
Drive 0 partition 1 is the EFI partition where CLOVER is installed which is not visible in the photo.
Drive 0 partition 2 contains MacOS.

 

[RehabMan]

Hi everyone,
I have tried over and over again to install Windows 10 on the same SSD (the only one I have on my laptop) but I always get the same error.
The procedure I have followed is this one.
1)I have installed MacOS with Clover UEFI after setting the BIOS:

• LEGACY SUPPORT
• UEFI first
• Disable fast boot
• Disable secure boot

2)I partitioned the drive with:

• MacOS (already installed) -> APFS
• Windows10 -> MacOS Extended Journaled (about 60gb)

3)I have booted into Windows 10 EFI from boot menu using both a USB 2 and 3 port.
ALTERNATIVE 1
4)I have deleted Windows10 partition and created a new one
5)I get this error when selecting the primary partition created:
"We couldn't create a new partition or locate an existing one. For more information, see the Setup log files"
ALTERNATIVE 2
4)I have deleted Windows 10 partition and hit next
5)I get this error:
"Windows could not prepare the computer to boot into the next phase of installtion. To install Windows, restart the installation"

I will attach 2 photos I have taken of the errors.
Drive 0 partition 1 is the EFI partition where CLOVER is installed which is not visible in the photo.
Drive 0 partition 2 contains MacOS.

Correct way is to format (as NTFS, within the Windows installer) the placeholder HFS+J partition you created, then direct the installer to install to that partition.

 

[uchika96]

Correct way is to format (as NTFS, within the Windows installer) the placeholder HFS+J partition you created, then direct the installer to install to that partition.

I have just tried again to be sure it was partitioned to HFS+J correctly so I have done it via diskutil.
When I boot into Windows setup I can only delete the partition and not format it. When I delete it and create a new one I get the same error as ALTERNATIVE1. May I have to format the partition via diskpart?

 

[ben9923]

I have just tried again to be sure it was partitioned to HFS+J correctly so I have done it via diskutil.
When I boot into Windows setup I can only delete the partition and not format it. When I delete it and create a new one I get the same error as ALTERNATIVE1. May I have to format the partition via diskpart?

From my experience, I remember you should just select the unallocated space in the Windows installer after you delete the placeholder partition, then install the OS. No need to create an NTFS/whatever partition via the Windows installer.

 

[uchika96]

From my experience, I remember you should just select the unallocated space in the Windows installer after you delete the placeholder partition, then install the OS. No need to create an NTFS/whatever partition via the Windows installer.

After doing as you say I get an error as reported in ALTERNATIVE 2
Anyway those should be created anyway when hitting "Next" on the installer so we are back at the starting point.

 

[RehabMan]

I have just tried again to be sure it was partitioned to HFS+J correctly so I have done it via diskutil.
When I boot into Windows setup I can only delete the partition and not format it. When I delete it and create a new one I get the same error as ALTERNATIVE1. May I have to format the partition via diskpart?

Use diskpart.exe from cmd.exe. You can get a cmd.exe instance with Shift+f10.

 

[uchika96]

Use diskpart.exe from cmd.exe. You can get a cmd.exe instance with Shift+f10.

I still get the same error, could you explain me better which partitions and relative type to create in diskpart? I still assume I have to delete the HFS+J partition created from MacOS before creating them in diskpart right?

 

[RehabMan]

I still get the same error, could you explain me better which partitions and relative type to create in diskpart? I still assume I have to delete the HFS+J partition created from MacOS before creating them in diskpart right?

Just format the placeholder HFS+J partition to NTFS using diskpart.exe 'format' command.
If you are not familiar with diskpart, you should read the documentation.

 

[uchika96]

Just format the placeholder HFS+J partition to NTFS using diskpart.exe 'format' command.
If you are not familiar with diskpart, you should read the documentation.

This is the output I get when using diskpart.
I can't select the volume (placeholder HFS+J partition) because it is not visible to format it (with diskpart format).

 

[RehabMan]

This is the output I get when using diskpart.
I can't select the volume (placeholder HFS+J partition) because it is not visible to format it (with diskpart format).

No need to select a volume to format a partition. Format operates on the selected partition, not a selected volume.