Dual boots from a single physical drive

This thread is continued from Convert MBR Disk to GPT Disk in Windows 10

zbook: I did not understand your instructions. Anyway, I have created this thread. I have an internal or external drive with free space.

NavyLCDR: I ran the command and could create the Windows boot menu.

My present problem is with the BIOS boot menu and BIOS boot priority. My experiments indicate their behavior is not consistent. Previously when the drive was Legacy MBR, I was using only the BIOS menu and did not bother setting the BOOT Priority.
Now Windows menu is displayed or not depending on how I use BIOS menu or setting BIOS Boot Priority.
BTW: The mobo is Gigabyte AORUS X570 Ultra and F12 is for the BIOS boot menu and F2 for setting boot priority.
If the system drive is left connected and everything else is disconnected, the Windows fails to boot.

I would like to switch the boot Windows as I used to do with MBR , which is by switching the active partition. How can I get rid of the Windows menu? Deleting one of the two shown at the MSCONFIG/Boot tab?

Please run these bat scripts and post share links into this thread using one drive, drop box, or google drive.


https://www.tenforums.com/attachment...p_plus_log.bat

https://www.tenforums.com/attachment...iskparinfo.bat

https://www.tenforums.com/attachment...on_mbr2gpt.bat

BSOD - Posting Instructions | Windows 11 Forum


Open msconfig > boot tab > post an image or share link into this thread

Post a new image of disk management:
How to Post a Screenshot of Disk Management

Post an image or share link of the BIOS boot order.

churin said:

This thread is continued from Convert MBR Disk to GPT Disk in Windows 10

zbook: I did not understand your instructions. Anyway, I have created this thread. I have an internal or external drive with free space.

NavyLCDR: I ran the command and could create the Windows boot menu.

My present problem is with the BIOS boot menu and BIOS boot priority. My experiments indicate their behavior is not consistent. Previously when the drive was Legacy MBR, I was using only the BIOS menu and did not bother setting the BOOT Priority.
Now Windows menu is displayed or not depending on how I use BIOS menu or setting BIOS Boot Priority.
BTW: The mobo is Gigabyte AORUS X570 Ultra and F12 is for the BIOS boot menu and F2 for setting boot priority.
If the system drive is left connected and everything else is disconnected, the Windows fails to boot.

I would like to switch the boot Windows as I used to do with MBR , which is by switching the active partition. How can I get rid of the Windows menu? Deleting one of the two shown at the MSCONFIG/Boot tab?

You could create two EFI system partitions, one for each OS, and then you could select the one you wanted with the F12 boot menu. There is no such thing as active partitions on a GPT drive. Instead of looking for an active partition, UEFI looks for a specific folder and file structure and if it finds that specific structure, it adds it to it's boot list.

churin said:

Could you provide how to create another EFI system partition? I wonder which one presently has its EFI system partition.

You can find out what OSs are listed in the current EFI System Partition by running the command:
bcdedit

We need to see a current screenshot of disk management to help further:
How to Post a Screenshot of Disk Management

I'm curious as to why you don't want to use the standard Windows dual boot menu?

When available please post the share link results from the earlier post.

zbook:
My virus software suppressed opening those .bat files.
The following is the requested screenshots:
1) MSCONFIG Boot tab

2) BIOS Boot Priority Order:

3) Disk Management - After W10 is selected on the Windows Boot Menu

Bat files are always blocked by design.

After manual override they can run in the background.


Some third party antivirus software may interfere with running V2.

Please temporarily uninstall them as needed.

V2 will run smoothly with Microsoft Defender.


Please widen row for disk 1 > post a new image

zbook said:

Bat files are always blocked by design.
After manual override they can run in the background.
Some third party antivirus software may interfere with running V2.
Please temporarily uninstall them as needed.
V2 will run smoothly with Microsoft Defender.

Sorry, I would not uninstall it.

Please widen row for disk 1 > post a new image

Here is the requested screenshot:

It's not necessary to uninstall any antivirus.

See if the computer can run V2:

BSOD - Posting Instructions



If there are any problems post images or share links for any error messages or codes.

And if your willing, you can manually run the scripts.

If your not willing to manually run the scripts then copy and paste this into administrative command prompt: (there will not be any antivirus prompt)

sfc /scannow
dism /online /cleanup-image /restorehealth
chkdsk /scan

Post images or share links displaying the commands with results into this thread.



Open administrative command prompt and copy and paste (all commands at one time):

Code:

bcdedit /enum all
reagentc /info
diskpart
lis dis
lis vol
sel dis 0
det dis
lis par
sel par 1
det par
sel par 2
det par
sel par 3
det par
sel dis 1
det dis
lis par
sel par 1
det par
sel par 2
det par
sel par 3
det par
sel par 4
det par
sel par 5
det par
sel par 6
det par
sel par 7
det par
sel par 8
det par

Post images or share links displaying the commands with results into this thread.