Assistance creating hybrid MBR/GPT on High Sierra to allow Windows to install

Hi, thanks for your reply.

The output of diskutil list is as follows:

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_APFS Container disk2 109.8 GB disk0s2

3: Microsoft Basic Data BOOTCAMP 135.2 GB disk0s3

4: Apple_Boot 134.2 MB disk0s4

5: Apple_APFS Container disk1 754.9 GB disk0s5

/dev/disk1 (synthesized):

#: TYPE NAME SIZE IDENTIFIER

0: APFS Container Scheme - +754.9 GB disk1

Physical Store disk0s5

1: APFS Volume Mac Data 942.1 KB disk1s1

/dev/disk2 (synthesized):

#: TYPE NAME SIZE IDENTIFIER

0: APFS Container Scheme - +109.8 GB disk2

Physical Store disk0s2

1: APFS Volume Macintosh HD 22.9 GB disk2s1

2: APFS Volume Preboot 22.0 MB disk2s2

3: APFS Volume Recovery 503.9 MB disk2s3

4: APFS Volume VM 20.5 KB disk2s4

Hi, thanks again for your reply!

I'm not sure I fully understand what you've written unfortunately, I've got 2 recovery partitions? Interestingly, I just shut down my mac and booted holding the Option key to see whether there were one or two recovery partitions showing, and there were none, only the main Macintosh HD boot option was available! So thoroughly confused now...

Has something gone wrong because I created the extra 'Mac Data' 754GB partition to store my data separately?

I'm not sure what I should be doing now, how do I go about fixing the 2 Recovery partitions issue, and then could you please elaborate a bit more on how exactly to use the program you've suggested in order to create the MBR?

Thanks for all your help, sorry that this is a bit complicated for me!

Hi, I've just rebooted and this is the output of diskutil list:

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_APFS Container disk2 109.8 GB disk0s2

3: Microsoft Basic Data BOOTCAMP 135.2 GB disk0s3

4: Apple_Boot 134.2 MB disk0s4

5: Apple_APFS Container disk1 754.9 GB disk0s5

/dev/disk1 (synthesized):

#: TYPE NAME SIZE IDENTIFIER

0: APFS Container Scheme - +754.9 GB disk1

Physical Store disk0s5

1: APFS Volume Mac Data 958.5 KB disk1s1

/dev/disk2 (synthesized):

#: TYPE NAME SIZE IDENTIFIER

0: APFS Container Scheme - +109.8 GB disk2

Physical Store disk0s2

1: APFS Volume Macintosh HD 22.6 GB disk2s1

2: APFS Volume Preboot 22.0 MB disk2s2

3: APFS Volume Recovery 503.9 MB disk2s3

4: APFS Volume VM 20.5 KB disk2s4

I do but only of my old Sierra install, I've not connected my external disk since clean-installing High Sierra in case I screwed up and converted the Time Machine Backup to APFS. Additionally the partition sizes were different on my old set-up, thought I'd take the chance to improve and re-size things with a fresh install.

Well I don't mind leaving the big 754GB 'Mac Data' partition as APFS not ExFat, as it's I think impossible for Windows to see it as the first 4 partitions will always be EFI, Mac HD (High Sierra boot drive), the (hopefully just 1!) Mac recovery partition and then the Bootcamp partition?

Output of diskutil apfs list:

APFS Containers (2 found)

|

+-- Container disk1 ACCF769F-975A-4625-88D8-1F0DF5BC0141

| ====================================================

| APFS Container Reference: disk1

| Capacity Ceiling (Size): 754863767552 B (754.9 GB)

| Capacity In Use By Volumes: 185401344 B (185.4 MB) (0.0% used)

| Capacity Available: 754678366208 B (754.7 GB) (100.0% free)

| |

| +-< Physical Store disk0s5 9BB89D2D-A67D-4E23-9E56-0AC3C69E1BCC

| | -----------------------------------------------------------

| | APFS Physical Store Disk: disk0s5

| | Size: 754863767552 B (754.9 GB)

| |

| +-> Volume disk1s1 E8E4665C-8BB9-43CC-954F-79BF3DE2CBF8

| ---------------------------------------------------

| APFS Volume Disk (Role): disk1s1 (No specific role)

| Name: Mac Data (Case-insensitive)

| Mount Point: /Volumes/Mac Data

| Capacity Consumed: 958464 B (958.5 KB)

| FileVault: No

|

+-- Container disk2 BA8C8B7D-A156-41C1-B861-66C81EF59427

====================================================

APFS Container Reference: disk2

Capacity Ceiling (Size): 109754822656 B (109.8 GB)

Capacity In Use By Volumes: 23358906368 B (23.4 GB) (21.3% used)

Capacity Available: 86395916288 B (86.4 GB) (78.7% free)

|

+-< Physical Store disk0s2 830E2EE3-41EC-4E14-8EF8-359A7ED8278F

| -----------------------------------------------------------

| APFS Physical Store Disk: disk0s2

| Size: 109754822656 B (109.8 GB)

|

+-> Volume disk2s1 0526DC99-D53F-3D5F-B277-0869D2F7E855

| ---------------------------------------------------

| APFS Volume Disk (Role): disk2s1 (No specific role)

| Name: Macintosh HD (Case-insensitive)

| Mount Point: /

| Capacity Consumed: 22707634176 B (22.7 GB)

| Encryption Progress: 20.0% (Unlocked)

|

+-> Volume disk2s2 572D7396-FF7C-4AF4-84F8-331D38939905

| ---------------------------------------------------

| APFS Volume Disk (Role): disk2s2 (Preboot)

| Name: Preboot (Case-insensitive)

| Mount Point: Not Mounted

| Capacity Consumed: 22003712 B (22.0 MB)

| FileVault: No

|

+-> Volume disk2s3 2CC0DE27-4026-4C9B-9B2B-5DD4A9ACCC86

| ---------------------------------------------------

| APFS Volume Disk (Role): disk2s3 (Recovery)

| Name: Recovery (Case-insensitive)

| Mount Point: Not Mounted

| Capacity Consumed: 503939072 B (503.9 MB)

| FileVault: No

|

+-> Volume disk2s4 D075F0DE-E3B3-49E5-ABAC-6CA99F1C73AA

---------------------------------------------------

APFS Volume Disk (Role): disk2s4 (VM)

Name: VM (Case-insensitive)

Mount Point: /private/var/vm

Capacity Consumed: 20480 B (20.5 KB)

FileVault: No

Thank you again for all of your help so far.

I'm assuming that the Apple_Boot recovery partition should be kept, in case I have any issues with High Sierra at some point? My iMac is too old to have Internet Recovery, I guess that means I need to have a physical recovery partition on the disk in case of booting issues?

Thank you thank you thank you!! You're a genius it worked!!

Currently writing this from Windows 10, successfully installed!

Thank you so much for your help, really appreciate it! It's magnificent of you to give up your time to help people struggle through these issues, and I've learnt a bit in the process! I'll be honest, I didn't have much hope of getting this to work before I posted here, but it's all working! Still got some minor teeething issues (initially the Apple Magic Mouse and keyboard were just working in very basic mode, then after installing the Bootcamp drivers the mouse allowed scrolling whilst the keyboard failed completely and had to use an USB keyboard. Currently keyboard working great and mouse back into basic mode, no scrolling.)

Overall, extremely happy to get it all working again, and thank you again for your wise words!

In case anyone finds this in the future and has similar issues, this is what I did from this point onwards (note, this is for a late-2009 21.5 inch iMac):

1. Followed Loner T's instructions on the thread he linked to to create/edit the hybrid MBR. This worked perfectly (just read the instructions carefully!)

2. I used Microsoft's Media Creation Tool (on a Windows PC) to create a 64-bit Windows 10 Fall Creator's Edition (1709) installation DVD. You can do this on a Mac too, I believe the website just allows you to download the ISO file directly and then you can burn that to DVD.

Note: I read a few reports on the internet that you need to install the Anniversary Edition (1607) of Windows 10 as later editions cause issues, and then use Windows Update to bring youself up-to-date with the lastest version. Microsoft seem to have taken down the older versions of Windows 10 and you can only download the latest one, Fall Creator's Edition. This worked fine for me, so don't worry about trying to track down the older version!

3. Put the DVD into my iMac and shut down, held down the C button on my keyboard whilst pressing the power button to boot from the Windows 10 installation DVD.

Note: I remember when installing Windows 7 (from DVD) many years ago that you needed to download & install some drivers from Apple onto a USB stick and keep that plugged in during the entire Windows installation, as otherwise you'd just get a black screen at a certain point during the installation process and nothing would proceed. I spent a while on the internet looking for these drivers, eventually found a copy I had backed up and put them on the USB. This just made the Windows 10 DVD installation process error immediately. Took the USB out and tried again and it worked fine. So you do not need to create this USB for drivers anymore, the Windows 10 Fall Creator's Edition installation media appears to contain the correct drivers itself.

4. Ran the Windows 10 installation, formatted my FAT32 drive to NTFS and Windows installed itself (pretty quickly, impressed!)

5. At this point then restarted and proceeded to boot into macOS. You need to eject the Windows 10 DVD, then shut down and hold down the Option button on your keyboard whilst powering on to get to the boot menu again. Choose Windows to boot from your Windows (bootcamp) partition and then the Windows Setup will continue and complete from there.

6. At this point, you're pretty much done! As stated above, my Apple Magic Mouse and keyboard were working in a very basic mode, but the Bluetooth, WiFi and screen were all working perfectly. I downloaded the Bootcamp drivers for Windows 7 from Apple's website (BootCamp4.0.4033) and unzipped them. Had a few errors trying to run the setup file, you need to right-click on it and click on Properties, then go to the Compatability tab and choose to run it in compatability mode for Windows 7. Even then it errored and blue-screened first time, tried it again and it mysteriously worked.

7. The Bootcamp drivers got my mouse working ok, but the keyboard now lost connection completely and pressing the power button on the keyboard did nothing. Had to use a USB keyboard to log-in, then open Settings, click on Devices and ensure you're in 'Bluetooth and other devices' on the left hand side. At the top, click to Add a Bluetooth device and the keyboard should then pair.

8. I then went back to the BootCamp4.0.4033 folder I'd downloaded, went to Bootcamp>Drivers>Apple>x64 folders and did the Windows 7 compatability trick again for AppleKeyboardInstaller64 and AppleWirelessMouse64 before running them both.

9. Lastly, (for UK people, no idea if this is needed for US) to get the @ and " symbols to work correctly on the keyboard, I went to Settings, clicked on Time & Language, then clicked on Region & language on the left hand side. At the bottom, under Languages, it should say English (United Kingdom) Windows display language. Click on this, then click on Options. On the next page, click on Add a keyboard, and select United Kingdom (Apple). I then deleted the other keyboard.

Hope that helps anyone else who might be clean-installing Windows 10 on their old machine, I've still got the scrolling issue on my mouse so will update if I sort that little issue out.

Thank you again to Loner T for all the assistance, a genuine star!