Moving MBR to other disk, problem "must be primary"

txsf

Member
Hello!

System is Win 10, Legacy (MBR) mode. Have a few disks, but the two ones that concern the problem are MBR (and NTFS), shown as Disk 0 and disk 2 on the attached picture. The Win10 disk is disk 0. (Some other disks are GPT but only data disks.)

Yesterday I converted the Windows disk 0 to GPT as I needed to switch to UEFI for some reasons. According to the software it was done correctly, but impossible then to boot in UEFI, so I reversed disk 0 to MBR and reversed the system to LEGACY... I thought it would bring back to old situation. But... Impossible to boot now ! Windows "repair" couldn't do anything.

So I decided to reinstall windows 10 on the disk 2 that was empty. OK, installed, running. But I wanted to use my Win old installation on disk 0. So I installed EasyBCD on disk 2 (new windows), and added an entry pointing to disk 0.

I set the BIOS to boot win disk 2, I have now the menu for both Win copies. I select the second one and OK, I can boot into my "old" windows on Disk 0. Good. (BCD config below)
(Something strange here, when I select the Windows on disk 0, the computer reboots and runs directly the expected version)

But the MBR is on disk 2 (in H:smile:. I would like to move it to disk 0 so that I can wipe disk 2 and use for something else.

As shown on picture, C: is on disk 0, primary partition, boot.
And the system partition is on disk 2 in H:

Using EasyBCD (from Win in disk 0) in BCD Backup/Repair I tried to "change boot drive" to C:... and get the message "...The boot partition must be a primary partition"...

But the wanted boot partition (C:smile: is already a primary one....

What to do so all files go to disk 0, and I can wipe disk 2?

Thank you !


PS. By the way there is a J: partition in disk 0, probably created when I converted to GPT, not sure. Inside is :

EFI
-- BOOT
-- BOOTX64.EFI
-- Microsoft
-- BOOT
-- BCD file
-- BOOT.STL file
-- BOOTMGFW.EFI file
-- BOOTMGR.EFI file
-- MEMTEST.EFI file
and languages directories


BCD config:

There are a total of 2 entries listed in the bootloader.

Default: Windows 10
Timeout: 30 seconds
Boot Drive: H:\

Entry #1
Name: Windows 10
BCD ID: {default}
Drive: H:\
Bootloader Path: \Windows\system32\winload.exe

Entry #2
Name: Microsoft Windows
BCD ID: {current}
Drive: C:\
Bootloader Path: \Windows\system32\winload.exe
 
I've never convered an OS from MBR/BIOS to GPT/UEFI, only clean installed in either mode, so I don't know exactly what the resulting disk would look like, but it looks as though your J partition is what would be the EFI System Partition under UEFI.
Now that you've converted back, it's still marked active, therefore would be the place where the MBR tries (unsuccessfully) to boot from.
I suspect that the 599Mb unlettered partition at the start of disk 0 is your original MBR location of the boot files.
Try flipping the active flag on disk 0 to there instead of J.
 
Hello!

Thanks for your reply. In fact as I couldn't MOVE the MBR ("needs to be primary etc") I tried to "deploy BCD" and make the partition bootable.

It worked :smile: In LEGACY, so... I gave up with UEFI, really don't want to reinstall then restore all Windows from backup...

I did it to install dualboot with Ubuntu, better in UEFI, but finally could do all the stuff in LEGACY !

Just want to add that I tried to use your Easy Recovery Essentials (before "deploying BCD"), it couldn't help, didn't find anything.

Best regards!
 
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