How to have one partition, instead of 3 (or more) when installing Windows 11

Question

I downloaded Windows 11 version 22H2 from Microsoft here. When I run Setup & get to the part of selecting the partition (NOT MY screen capture):

I can't simply select a single large enough, just-formatted, NTFS partition to which Setup will install Windows & also pack System/Recovery together with it, resulting in a single partition. Remember this is the procedure back back to Windows 10, at least. Instead, it has me providing an unallocated space by preparing one before setup or deleting a partition at this point. To which then I click on New creating at least 3 partitions (System + Primary + Recovery, typically), where you choose the Primary to install Windows 11 at, or simply click Next.

How do I make the Setup make do with just one partition? Put the System &/or Recovery together with Windows in the same partition?

Answer 1

What you want to achieve is possible but with a few caveats

1. Download Windows 10 ISO using Media Creation Tool
2. Download Windows 11 ISO using Media Creation Tool
3. Using Rufus create a BIOS bootable USB installer of Windows 10 (NO UEFI Mode)
4. Mount Windows 11 ISO and replace the install.esd from Windows 10 installer with install.esd from Windows 11 ISO. In short we now wrap install.esd of Windows 11 in Windows 10 installer. Location \sources folder therein
5. In your PC firmware set or enable Legacy / CSM Mode (If your system is Class-3 UEFI this won’t be possible and full stop here)
6. Boot to your system using third-party Windows PE based boot disks like Hiren Boot DVD. If you don’t have DVD drive create a BIOS bootable USB installer
7. Go to Control Panel -> Create partitions options and initialize the disk to MBR and create one full single NTFS partition all along the length of the disk. Alternatively if you already have other partitions, there should be no free space left on the drive. It needs to be MBR format not GPT. Create your system NTFS partition upfront in such a way that there's no free space left anywhere on the drive
8. Restart and boot your PC now using the Windows 10 installer USB (Inside which resides install.esd from Windows 11)
9. When you reach ‘Where you want to install Windows’ just select the whole partition and there’s no free space left anywhere
10. Windows will begin and eventually complete the installation of Windows 11 on a single partition

Note the following

You lose recovery partition to my knowledge with this approach

This is unsupported configuration. Might have latent issues.

Now shrink Windows system partition if you want. Ultimately your Windows 11 uses only one system partition all along

This is possible but not recommended

See screenshots from my tryouts in VMWare VM. Not tested if will behave the same way on real hardware. You may try if you want to.