Solved HELP: Two Windows 11 in two different disks (drives) boot only by F12

Hi,

I have two disks (let's call them A and B). A is a SSD, and B is a HDD.
At A and B I have two Windows 11 Pro version 10.0.22621 Build 22621 (let's call them W1 in disk A, and W2 in disk B).
W1 and W2 are botting with the typical Windows Dual Boot (I mean the Windows boot menu that loads at device startup, and user can choose if W1 or W2 is going to be launched).

Please, I need to replace my current Windows Dual Boot method with the F12 method.
In simple words, I need to boot W1 or W2, (only) by pressing F12 (only by choosing disk A or B).
So, I need to eliminate any boot relation between W1 and W2, no more Windows Dual Boot, no more menu at device startup etc). I need a clean and totally separated boot method, which will work only when F12 is pressed, and disk A or B is chosen as the botting disk.

Please, is it possible?
Please, can you help me? Please can you explain me step by step how to do it?
I expended several hours googling the subject, unfortunately couldn't find an answer. And when I found some possible explanations, sadly it was too techy for my level.

Any help will be more than welcome, and thank you in advance!

The good news is that it is super easy to accomplish. Open a command prompt with admin privileges and run:

Post the results.

NavyLCDR said:

The good news is that it is super easy to accomplish. Open a command prompt with admin privileges and run:

Code:

diskpart
select disk 0
list part
select disk 1
list part
list volume

Post the results.

Click to expand...

Hi @NavyLCDR

Firstly, thank you for your great help!

Attached below the results you requested. Before that and if it helps, please let me add some info:

1. Disk 0 is the HDD, considered as second disk.

2. Disk 1 is the SSD, considered as main disk.

3. Both disks have Windows, but Windows at disk 1 (SSD) is the Windows default of the combo (the Windows that should boot at every device startup, according to my F12 booting drive order).

4. Windows at disk 1 (SSD) uses four partitions:

Partition 1 System 100 MB
Partition 2 Reserved 16 MB
Partition 3 Primary 60 GB
Partition 4 Recovery 699 MB

and

Volume 14 FAT32 Partition 100 MB Healthy System
Volume 7 C SO NTFS Partition 60 GB Healthy Boot
Volume 15 New Volume NTFS Partition 699 MB Healthy Hidden

Windows folders are in Volume 7, Partition 3.
WinRE (Recovery) is in a separated partition: Volume 15, Partition 4.

5. Disk 1 (SSD) contains Strelec disk (bootable with F12) at Partition 5, Volume 5.

6. Disk 0 (HDD) contains Strelec disk (bootable with F12) at Partition 2.

7. Windows at Disk 0 (HDD) uses Partition 1.

THE RESULTS OF THE CODE YOU REQUESTED:

Microsoft Windows [Version 10.0.22621.1635]
(c) Microsoft Corporation. All rights reserved.

C:\Windows\System32>diskpart

Microsoft DiskPart version 10.0.22621.1

Copyright (C) Microsoft Corporation.
On computer: ABC

DISKPART> select disk 0

Disk 0 is now the selected disk.

DISKPART> list part

Partition ### Type Size Offset
------------- ---------------- ------- -------
Partition 1 Primary 70 GB 1024 KB
Partition 2 Primary 10 GB 70 GB
Partition 3 Primary 20 GB 80 GB
Partition 4 Primary 50 GB 100 GB
Partition 5 Primary 118 GB 150 GB
Partition 6 Primary 20 GB 268 GB
Partition 7 Primary 10 GB 288 GB

DISKPART> select disk 1

Disk 1 is now the selected disk.

DISKPART> list part

Partition ### Type Size Offset
------------- ---------------- ------- -------
Partition 1 System 100 MB 1024 KB
Partition 2 Reserved 16 MB 101 MB
Partition 3 Primary 60 GB 117 MB
Partition 4 Recovery 699 MB 60 GB
Partition 5 Primary 10 GB 60 GB
Partition 6 Primary 20 GB 70 GB
Partition 7 Primary 50 GB 90 GB
Partition 8 Primary 306 GB 140 GB
Partition 9 Primary 19 GB 446 GB
Partition 10 Primary 9 GB 466 GB

DISKPART> list volume

Volume ### Ltr Label Fs Type Size Status Info
---------- --- ----------- ----- ---------- ------- --------- --------
Volume 0 D SO2 NTFS Partition 70 GB Healthy
Volume 1 F EM2 NTFS Partition 10 GB Healthy
Volume 2 H PRTB2 NTFS Partition 20 GB Healthy
Volume 3 J STRG2 NTFS Partition 50 GB Healthy
Volume 4 L DEL2 NTFS Partition 118 GB Healthy
Volume 5 W SOS2 FAT32 Partition 20 GB Healthy
Volume 6 Y TRSH2 NTFS Partition 10 GB Healthy
Volume 7 C SO NTFS Partition 60 GB Healthy Boot
Volume 8 E EM NTFS Partition 10 GB Healthy
Volume 9 G PRTB NTFS Partition 20 GB Healthy
Volume 10 I STRG NTFS Partition 50 GB Healthy
Volume 11 K DEL NTFS Partition 306 GB Healthy
Volume 12 V SOS FAT32 Partition 19 GB Healthy
Volume 13 Z TRSH NTFS Partition 9 GB Healthy
Volume 14 FAT32 Partition 100 MB Healthy System
Volume 15 New Volume NTFS Partition 699 MB Healthy Hidden

DISKPART>

Whew! If any command fails, do not move on to the next command! From the above information:

NavyLCDR said:

Whew! If any command fails, do not move on to the next command! From the above information:

Code:

diskpart
select disk 0
select part 1
shrink desired=100
create part EFI
format fs=fat32 quick
assign letter=s
exit
bcdboot D:\Windows /s S: /f UEFI
diskpart
select volume s
remove
exit
exit

Click to expand...

Thank you again @NavyLCDR
Just for the sake of learning, please, may I ask you the following simple questions?

1. From my ignorance, your steps of commands seem to create a 100MB partition in disk 0, which makes bootable the Windows there. Am I right?

2. The the second group of "diskpart" steps starts with "select volume s". How this specific "diskpart" knows if "volume s" is in disk 0 or disk 1? Is not necessary first to "select disk" and "select part"?

3. What is the "volume s"? Why is removed?

4. Changing subject:
When I installed the second Windows in the second drive (HDD), I used an external USB with the Windows Media Creation Tool, and clearly it detected my already installed Windows in my first drive (SSD). And that's the reason why now I have the undesirable Windows Dual Boot.
Please, my question is what happens if I disconnect my first drive (SSD), I delete the Windows in my second drive HDD (deleting partition etc), and I try again a new Windows installation in my second drive (HDD)? From my ignorance, if I do that, Windows Media Creation Tool is going to create an independent bootable Windows in second drive (HDD), which is going to have its own 100MG UEFI bootable partition. Am I wrong?
And is this method going to work when I reconnect the first drive (SSD)? I mean, am I going to be able to boot both Windows by pressing F12 and choosing a specific drive?

Please, answer me only if you want and when you can.
Again, zillions of thanks for your amazing help!

Decopi said:

Thank you again @NavyLCDR
Just for the sake of learning, please, may I ask you the following simple questions?

1. From my ignorance, your steps of commands seem to create a 100MB partition in disk 0, which makes bootable the Windows there. Am I right?

2. The the second group of "diskpart" steps starts with "select volume s". How this specific "diskpart" knows if "volume s" is in disk 0 or disk 1? Is not necessary first to "select disk" and "select part"?

3. What is the "volume s"? Why is removed?

4. Changing subject:
When I installed the second Windows in the second drive (HDD), I used an external USB with the Windows Media Creation Tool, and clearly it detected my already installed Windows in my first drive (SSD). And that's the reason why now I have the undesirable Windows Dual Boot.
Please, my question is what happens if I disconnect my first drive (SSD), I delete the Windows in my second drive HDD (deleting partition etc), and I try again a new Windows installation in my second drive (HDD)? From my ignorance, if I do that, Windows Media Creation Tool is going to create an independent bootable Windows in second drive (HDD), which is going to have its own 100MG UEFI bootable partition. Am I wrong?
And is this method going to work when I reconnect the first drive (SSD)? I mean, am I going to be able to boot both Windows by pressing F12 and choosing a specific drive?

Please, answer me only if you want and when you can.
Again, zillions of thanks for your amazing help!

Click to expand...

The first set of diskpart commands will shrink the existing Windows partition on Disk 0 and create an EFI system partition in the free space created, format it and give it drive letter S. But it will just be an empty partition

The bcdboot command takes the boot files from D:\Windows and the puts them in the new system partition, which is what really makes it bootable.

The second set of diskpart commands will simply select whatever partition is assigned to drive letter S and it will remove the drive letter from the partition. It will not delete the partition itself, nor will it do anything to any of the files in the partition, it only removes the drive letter from it.

If you were to remove the Windows partition on disk 0 and left that space unallocated. Then physically disconnected or removed disk 1. Then used a Windows 11 USB flash drive to do a clean install on disk 0 - selecting the unallocated space to install to, yes, Windows setup would make all of the partitions needed to boot from disk 0 on it's own. When you reconnected disk 1, you could select either disk to boot from with the F12 menu.

Decopi said:

Thank you again @NavyLCDR
Just for the sake of learning, please, may I ask you the following simple questions?

1. From my ignorance, your steps of commands seem to create a 100MB partition in disk 0, which makes bootable the Windows there. Am I right?

2. The the second group of "diskpart" steps starts with "select volume s". How this specific "diskpart" knows if "volume s" is in disk 0 or disk 1? Is not necessary first to "select disk" and "select part"?

3. What is the "volume s"? Why is removed?

4. Changing subject:
When I installed the second Windows in the second drive (HDD), I used an external USB with the Windows Media Creation Tool, and clearly it detected my already installed Windows in my first drive (SSD). And that's the reason why now I have the undesirable Windows Dual Boot.
Please, my question is what happens if I disconnect my first drive (SSD), I delete the Windows in my second drive HDD (deleting partition etc), and I try again a new Windows installation in my second drive (HDD)? From my ignorance, if I do that, Windows Media Creation Tool is going to create an independent bootable Windows in second drive (HDD), which is going to have its own 100MG UEFI bootable partition. Am I wrong?
And is this method going to work when I reconnect the first drive (SSD)? I mean, am I going to be able to boot both Windows by pressing F12 and choosing a specific drive?

Please, answer me only if you want and when you can.
Again, zillions of thanks for your amazing help!

Click to expand...

Amazing answers and help @NavyLCDR
Thank you once again!

Please, last question: What about the current Windows Dual Boot in my SSD = disk 1? Do I need to remove, or delete or clean it?
I mean, and just to be clear, even if I apply your steps, making the second Windows bootable at the second drive (HDD), and choosing to boot from disk 0 or disk 1 by pressing F12 etc... right now I still have the undesirable Windows Dual Boot in my main drive (SSD = disk 1). Do I need to remove it?

Decopi said:

Amazing answers and help @NavyLCDR
Thank you once again!

Please, last question: What about the current Windows Dual Boot in my SSD = disk 1? Do I need to remove, or delete or clean it?
I mean, and just to be clear, even if I apply your steps, making the second Windows bootable at the second drive (HDD), and choosing to boot from disk 0 or disk 1 by pressing F12 etc... right now I still have the undesirable Windows Dual Boot in my main drive (SSD = disk 1). Do I need to remove it?

Click to expand...

It is not essential but if you wish to, remove the boot entry by running msconfig, select boot tab, delete uneanted entry (be careful you choose right onel.