I want two Mac OS partitions and one Windows (Bootcamp)

[Geitekaas]

Hello dear people,

I have seen a few old postings, more or less about this subject. But after so many years I think it's time to ask for a sort of an update.

On my MacPro I use OpenCore, so no problem there. On my MacMini 2012, I also have OpenCore, with Sonoma. No problem there also.
I just bought a 2019 16" MacBook Pro for my wife. Beware, this is an Intel, not a Silicon Valley one. It's a beast. Here is what I want:

•I want Sonoma native for usual daily work.
•I want Mojave for a few old apps, mostly some games (I know the workaround to install Mojave on this T2 chip).
•I want Windows 10.

I know about Parallels, I have a registered copy. I doesn't suffice for my purposes. I really hope that this thread does not turn into a heated debate whether to use or not use Windows or Parallels.
I know that there is a solution. I've done a lot of searching. I would like to distance myself from OpenCore, because this machine has native Sonoma on it.

As I see it, one of the options is to install either Mojave first, or Sonoma; let Bootcamp Assistant make a bootcamp partition. Then, without installing Windows, go back into either MacOs and let Disk Utility add another partition. E.g., if I installed Sonoma first, the other partition would be the place where I could install Mojave. But before installing the second OS, I would have to install Windows on the bootcamp partition, right?

Another option would be to install Sonoma and Bootcamp with Windows, and then try to make an extra partition and install Mojave on that.

I am afraid that either option would mess up my Bootcamp though.
I have read that trying to add Bootcamp when you have two partitions, Bootcamp will not install.


So, my question is: does anybody have any experience or advice to make this happen:
Two partitions with two different MacOS'es & one Windows partition (10 or 11, I don't care), and this all without OpenCore.


I really hope there is somebody out there who has a solution! I don't want to spend days of installing and de-installing without some good old advice from someone that has already been there.

Looking forward to some answers. Have a great day!

 

[carylee2002]

With all those operating systems on your system drive may limit how much HD space you have left. You might consider installing one of the MAC OS system on a zip or SSD drive and just install Sonoma and Win 10 on the computer. Then boot up the SSD with Mojave when needed.

 

[headlessmike]

Hello dear people,

I have seen a few old postings, more or less about this subject. But after so many years I think it's time to ask for a sort of an update.

On my MacPro I use OpenCore, so no problem there. On my MacMini 2012, I also have OpenCore, with Sonoma. No problem there also.
I just bought a 2019 16" MacBook Pro for my wife. Beware, this is an Intel, not a Silicon Valley one. It's a beast. Here is what I want:

•I want Sonoma native for usual daily work.
•I want Mojave for a few old apps, mostly some games (I know the workaround to install Mojave on this T2 chip).
•I want Windows 10.

I know about Parallels, I have a registered copy. I doesn't suffice for my purposes. I really hope that this thread does not turn into a heated debate whether to use or not use Windows or Parallels.
I know that there is a solution. I've done a lot of searching. I would like to distance myself from OpenCore, because this machine has native Sonoma on it.

As I see it, one of the options is to install either Mojave first, or Sonoma; let Bootcamp Assistant make a bootcamp partition. Then, without installing Windows, go back into either MacOs and let Disk Utility add another partition. E.g., if I installed Sonoma first, the other partition would be the place where I could install Mojave. But before installing the second OS, I would have to install Windows on the bootcamp partition, right?

Another option would be to install Sonoma and Bootcamp with Windows, and then try to make an extra partition and install Mojave on that.

I am afraid that either option would mess up my Bootcamp though.
I have read that trying to add Bootcamp when you have two partitions, Bootcamp will not install.


So, my question is: does anybody have any experience or advice to make this happen:
Two partitions with two different MacOS'es & one Windows partition (10 or 11, I don't care), and this all without OpenCore.


I really hope there is somebody out there who has a solution! I don't want to spend days of installing and de-installing without some good old advice from someone that has already been there.

Looking forward to some answers. Have a great day!

I would do pretty much as you state, with perhaps one minor difference. Start with a version of macOS, e.g. Sonoma, and use Bootcamp Assistant to make a bootcamp partition. But instead of adding another partition for another version of macOS, you add a container to your existing APFS partition (with the + Volume button in Disk Utility). Containers within a single partition share the available disk space, so you don't need to worry about how much you allot to each OS. They are also easy to wipe if you need to without affecting the other volumes. I don't run Windows, so I cannot make any guarantees, but I do have a few different copies of macOS running in a single APFS partition this way.

 

[Snowlover]

I would start with the windows partition, install without bootcamp (but add the drivers).Erase the entire internal drive from the windows install usb, format and install.
Then make free space at the end of the windows partition, then format to apfs (using an external bootable clone of macos would be easiest for the formatting).
Then either clone to or install onto this partition, create new container and clone to or install second macos onto this.
This way any changes to macos partition/containers shouldn't affect the windows install, because it isn't dependent on bootcamp/macos.
Please correct me if I am wrong on this.