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APFS on MBR

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Jul 26, 2012
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My computer is pretty old and doesn't have a UEFI so I have to keep MBR to boot Windows.
I always have Windows and macOS on the same SSD. When macOS started to check if partition is GPT during update I would temporarily change it.
So when I was installing Catalina I changed partition scheme to GPT as always, it works fine no problems there. But now when I revert back to MBR Clover doesn't see APFS partition (before I always used HFS+). I set partition type to 0xAF but to no avail. So is there some method to boot APFS partition on MBR using Clover?
 
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Sorry to hijack this thread. How do you temporarily change the partition scheme from MBR to GPT and back? I too have older machine and have El Capitan installed on MBR. I've love to try this.
 
Joined
Jul 26, 2012
Messages
36
Motherboard
Asus P5Q Deluxe
CPU
Intel Core 2 Quad Q9550
Graphics
GeForce GT 730
I was using dd with previously prepared MBR and GPT files.

I actually managed to solve my problem. I was playing with hybrid MBR but no matter what I did Windows 7 was always getting stuck on booting logo. To make it work I would have to reinstall it with hybrid MBR present. But I didn’t want to do that. I noticed that for whatever reason Windows 7 will stuck on logo if there is GPT partition table on sector 2 (counting from 0) despite it being masked by 0xEE MBR entry. So I move it to sector 3, modified GPT header (LBAs and CRCs, including backup). And now it works even better than before. I no longer have to change MBR for macOS updates. Windows sees disk as MBR and macOS as GPT.

My MBR partition list:

1 0xEE from 1 to 12 287 (this lets macOS recognize disk as GPT)
2 0x07 from 12 288 to 402 665 471 (Windows 7 x64) boot
3 0x0C from 402 665 472 to 403 279 871 (EFI with Clover)
4 0xAF from 403 279 872 to 488 392 704 (Catalina)

I don’t think that positions 3 and 4 have to be exposed in the MBR but I prefer it that way.
I use Windows’s BCD to start Clover and boot macOS.

And one more thing that I found during this research is that when I added GPT to my disk but there was no 0xEE MBR entry Clover would see APFS partitions and when I select it macOS would start booting (progress bar and apple logo) but after a while prohibited sign would show up. Therefore I think it is impossible to boot macOS using APFS on pure MBR disk.

At first they were checking for GPT during macOS installation, then they started additionally required it for system updates and now GPT is required for everyday system booting.
 
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