MBG2GPT and WinRE issue

Hi all - I've been trying to upgrade Win10 to 11, but to do that I need to go from MBR to UEFI and have run into a problem.

I used MGB2GPT - I first tried to do offline via WindowsRE, but couldn't log in to RE cmd prompt even though I verified my email and password were correct... Now, I should have stopped there, but instead I ran the tool through the admin cmd prompt using 'allowFullOS'.

I validated first, all fine, and the conversion looks to have worked, except for the WinRE error at the end:



I decided to shut down, try changing the bios to uefi - but it says 'shutting down', goes black, and then just goes back into windows. Windows is working so not sure I want to reset in case I can't boot!

Tried seeing if I could fix WinRE but basic stuff doesn't work:


All the other ideas I can find involve going into the Cmd prompt in Win RE - which I know I can't do due to the 'incorrect password' issue.

Should I just press the reset button and hope I can reboot (after changing from CMS to UEFI in bios)??

This has gone beyond my level of expertise now so any help appreciated!

Windows version: 22H2 (19045. 4291)

Are you in BIOS or UEFI now?

type cmd (admin)
bcdedit
does it show:
\Windows\system32\winload.efi or winload.exe ?

Pentagon said:

Are you in BIOS or UEFI now?

type cmd (admin)
bcdedit
does it show:
\Windows\system32\winload.efi or winload.exe ?

Hi Pentagon - I'm still in the Win10 environment as it didn't shut down when I clicked that (came up with the blue 'shutting down' screen and then went back into normal Win10) and I'm a bit nervous to push the reset button to force it! So I haven't gone back to the BIOS at all - so that will still be set at CMS legacy, but it looks like the GPT conversion did work...

This is the response I get to that inquiry:

C:\WINDOWS\system32>bcdedit
The boot configuration data store could not be opened.
The requested system device cannot be found.

click on keyboard "Windows" + "R" and in Run type msinfo32

There you should find if BIOS or UEFI

Run
C:\Windows\System32>diskpart
list disk
sel disk # (replace # by the diskno.)
list par
is there a Fat32 partition?
is there a (*) in the right column?

Edit: It should not take more than 5 minutes!

Pentagon said:

click on keyboard "Windows" + "R" and in Run type msinfo32

There you should find if BIOS or UEFI

Run
C:\Windows\System32>diskpart
list disk
sel disk # (replace # by the diskno.)
list par
is there a Fat32 partition?
is there a (*) in the right column?

Edit: It should not take more than 5 minutes!

Thanks - Msinfo gives 'BIOS Mode Legacy' - which would make sense as I've not gone back to the BIOS after doing the MGB2GPT conversion - so it'll still be set to CMS legacy there. (I was surprised windows still works but I guess that's because the bios isn't being used as I'm still in Windows?!)

I may have done this wrong but it doesn't give me a Fat32 listing, but there is a * under GPT column?

DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
-------- ------------- ------- ------- --- ---
Disk 0 Online 931 GB 0 B *
Disk 1 Online 931 GB 0 B
Disk 2 Online 2794 GB 7168 KB

DISKPART> sel disk 0
Disk 0 is now the selected disk.
DISKPART> list par
Partition ### Type Size Offset
------------- ---------------- ------- -------
Partition 1 Primary 100 MB 1024 KB
Partition 2 Primary 930 GB 101 MB
Partition 4 System 100 MB 930 GB
Partition 3 Recovery 557 MB 930 GB

There were three partitions before I ran MGB2GPT, now there are 4. Disk management lists the four partitions as below - one of the 100MB partitions is new (but not sure which!):

That's easy to fix, but I don't wait so long till I get an answer!
My time is limited

Let Megahertz try

Megahertz said:

Regarding the Recovery environment, it seems you don't have it. (Win RE is disabled and can't be enabled)

Please post a whole window Disk Manager image of ALL your drives. Don't forget to expand the columns so we can read them. How to Post a Screenshot of Disk Management
If you have a MiniTool or AOMEI Partition use it instead or Windows disk manager.

Hi Megahertz - thanks for your reply. Have updated system specs and main drive is SDD. I'll investigate that MCT tool and will action. Yes, I was thinking I don't have Win RE - would explain why I can't log into it - no idea why I don't have it...

Full screen Disk Manager:


- - - Updated - - -

Pentagon said:

That's easy to fix, but I don't wait so long till I get an answer!
My time is limited

Let Megahertz try

Sorry, am not as fast as that, thanks for getting me this far.

@ricardomax

OK 1.step

run cmd (admin)
C:\Windows\System32>diskpart
sel disk 0
sel par 1
format quick fs=fat32 label="System"
assign letter=S
set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b
gpt attributes=0X8000000000000000
exit
bcdboot C:\Windows /s S: /f UEFI

watch the system response after each input

try to run
bcdedit
reg query HKLM\SYSTEM\CurrentControlSet\Control /v FirmwareBootDevice


post result

Only when BCD output is OK you can shutdown and boot into BIOS and switch to UEFI!

Pentagon said:

@ricardomax
format quick fs=fat32 label="System"
assign letter=S
set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b
gpt attributes=0X8000000000000000
exit

Thanks Pentagon for your reply, much appreciated. I got to the format line then get an error:

DISKPART> format quick fs=fat32 label="System"

Virtual Disk Service error:
Format is not allowed on the current boot, system, pagefile,
crashdump or hibernation volume.