Moving mbr fron one hdd to another

Volume Z · 04 Jan 2024

Megahertz said:

On a Windows Legacy-MBR you can set Windows partition as Active and BIOS will transfer the boot sequence to the MBR that will transfer directly to Windows partition.

No. You'll render the installation unbootable by moving the "active" mark to a partition that holds no boot manager. It will result in BOOTMGR IS MISSING even on the Windows partition.

BUT as opposed to GPT the Windows partition can become the partition that holds the boot manager.

Megahertz · 04 Jan 2024

Volume Z said:

No. You'll render the installation unbootable by moving the "active" mark to a partition that holds no boot manager. It will result in BOOTMGR IS MISSING even on the Windows partition.

BUT as opposed to GPT the Windows partition can become the partition that holds the boot manager.

Yes. Have done it more than once.

Volume Z · 04 Jan 2024

Me too...

Before:

Moving mbr fron one hdd to another-before.png

After:

Moving mbr fron one hdd to another-failed.png

Megahertz · 04 Jan 2024

Did you run
bcdboot C:\Windows /s C: /f BIOS ?

Ativo = Active
Inicialização = Boot

Moving mbr fron one hdd to another-dmx.png

SIW2 · 04 Jan 2024

Askic said:

Thank you very much!
This solved the problem!

- - - Updated - - -

I also see that partition with Windows installation folder should be marked as boot. Can you explain that? Why is for example C marked as boot partition ewhen boot sector is actually on the hidden system reserved partition?

Microsoft describes the partition booted from as system ( it contains the boot critical files )

Microsoft describes the partition you are booted into as boot ( it contains the operating system)

It sounds odd but that is what they do.

with mbr the bios will hand control to the mbr code which then passes control to the pbr code on the partition marked active. So the boot critical files need to be on the partition marked active.

Volume Z · 04 Jan 2024

Megahertz said:

Did you run
bcdboot C:\Windows /s C: /f BIOS ?

I did like you suggested...

Megahertz said:

set Windows partition as Active and BIOS will transfer the boot sequence to the MBR that will transfer directly to Windows partition.

Megahertz · 05 Jan 2024

Volume Z said:

I did like you suggested...

I wasn't giving anyone instructions on how to do it. I said it can be done.
You are the kind that don't recognize when you were wrong.
Anyway, I hope you've learned something new. Isn't that the reason why we are here?

Volume Z · 05 Jan 2024

Wrong at what? Quoting you?

I have always said that

Volume Z said:

the Windows partition can become the partition that holds the boot manager.

And yes, of course the partition can be marked as active. How could it not if System and Boot were unified by default in the days of XP and Vista. But still the partition requires startup files. The "Active" mark alone won't do.

Megahertz said:

you can set Windows partition as Active and BIOS will transfer the boot sequence to the MBR that will transfer directly to Windows partition.