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Hi there,
I have been trying to update to Windows 11 off-and-on again for the last year due to how difficult & frustrating this process has been.
I'm currently stuck as my drive with windows installed is on MBR and not GPT. The last time I attempted to convert this drive to GPT following multiple different guides months ago, it led to my PC booting into a BSOD and I had to spend 3 hours trying to revert everything.
I've tried once again, the PC health checker has given me all green ticks so I tried to run the Windows 11 installation assistance and got the error in the title (Error code: 0x80070003 - 0x40008).
I've added a google drive with as much info as I can grab and can add to this if anymore info/screenshots are needed.
https://drive.google.com/drive/folders/1KTKQE2_vTgLKDR4GMUray_OeY_SKpLHL?usp=sharing
I've included screenshot of disk management, the compatibility scan data, mbr2gpt logs, tuneup plus logs & the compatibility appraiser cmd logs I found in a similar post.
Please let me know if you need any further information.
Thank you!
BIOS update is available for your Motherboard.
https://www.asrock.com/mb/Intel/Z590%20Steel%20Legend/index.asp#BIOS
Maybe it will fix the boot issues. Windows 11 25H2 usually demands the latest BIOS. The version installed on your computer is somewhat outdated (2021).
Hi Ramesh,
Thanks for that, the link was for the wrong motherboard but I found the correct one and updated it. If I just wanted to do a fresh install/reset to do it the 'easier' way how would I do this? I have another SSD that is already on GPT but that is not my current windows install drive.
Hi Aiden,
After updating the BIOS, are you able to boot into WinRE?
If not, you can try to convert the OS disk to GPT using AOMEI (free). Please see How to Safely & Easily Convert MBR to GPT Without OS. Be sure to backup the data first, in case something happens during the conversion.
For cleanly installing Windows 11, the following tutorials can be helpful.
https://pureinfotech.com/clean-install-windows-11/#windows11_clean_install_usb
Note:
When installing Windows cleanly, it is recommended that all other hard drives be disconnected, especially if the EFI partition is located on one of them. Disconnecting the other drives ensures the EFI and MSR partitions are created on the new drive.
Hi Ramesh,
I'm finally on W11 after just accepting it and doing a fresh install on my other SSD. I now have a new problem that I'm hoping isn't permanent.
When I installed windows and confirmed I could log in etc. I powered off my PC and reconnected my other 2 drives and ensured my first SSD with the windows installation wasn't set as the boot device. All went fine and I could boot and log into W11 but when I tried to access my D drive (Hard drive without a windows 10 or 11 install on it) file explorer stopped responding and my bottom task bar completely disappeared (as part of file explorer not responding) so I restarted and when I restarted I was stuck on loading on the BIOS startup screen with a loading wheel and nothing happening.
I can boot into W11 fine with the hard drive disconnected, how can I go about fixing this without losing all my data?
Hi Aiden,
Can you connect the disk to another computer and access the data?
Some WD Internal drives need a firmware update so that they support Windows 11. What's the model number of the disk?
It's still booting in UEFI mode somehow.
Your best option is to create a USB setup disk and do the MBR2GPT conversion.
Hi Ramesh,
This is the output or attempt to run the above:
bcdboot C:\Windows /s C: /f BIOS
mbr2gpt /validate /disk:1 /allowfullOS
First command runs successfully:
but the 'Mark Partition as Active' is greyed out (for both the system reserved and C: partition):
I think the system has booted in UEFI mode, although the partition is MBR.
Can you boot into Windows RE?
Run:
reagentc /info
If Windows RE status is Enabled, please boot into Windows RE.
How to access the Windows Recovery Environment in Windows
In WinRE, click Troubleshoot, Advanced Options, Command Prompt.
Run:
Run:
mbr2gpt.exe /validate /disk:1
From the first command Windows RE status is 'disabled'
Ok. You can do one of the following:
Access Windows RE using a Windows 10 or 11 USB setup disk. Run MBR2GPT from WinRE.
(or)
Boot Windows in MBR/BIOS mode instead of UEFI mode. Once done, run MBR2GPT from Windows.
As I don't have a USB setup disk handy, how do I Boot Windows in MBR/BIOS mode instead of UEFI mode?
// how do I Boot Windows in MBR/BIOS mode instead of UEFI mode? //
What's your PC's make and model? Run msinfo32.exe and post a screenshot of the System Summary screen.
BIOS manual is here → https://download.asrock.com/Manual/Z590%20Steel%20Legend.pdf
As I don't have a USB setup disk handy
FYI: Here's how to create one using the Media Creation Tool. The contents of the USB disk will be erased.
I followed all the instructions above and CSM was already enabled and all settings except the last were set to 'legacy only' already.
Windows RE is still set to disabled
It's still booting in UEFI mode somehow.
Your best option is to create a USB setup disk and do the MBR2GPT conversion.
Image upload keeps failing but the only options under CSM were:
Launch PXE OpROM Policy
Launch Storage OpROM Policy
Other PCI Device ROM Priority
All of the above I've set to legacy only
Hi Ramesh,
I used the installation media to create a windows 11 bootable usb but everytime I boot from it and select 'Repair my PC' it just boots back to my normal windows install. I changed the boot options in my BIOS to only boot from the USB and it just keeps looping back to the option to select 'Repair my PC', restarts and does it again. I can fix this by changing back to my normal boot in BIOS but I cannot go into the windows recovery environment.
@Aiden:
Can you turn off CSM support and Legacy boot options and try booting from USB again?
Just tried this and still the same thing
Please try the Windows 10 USB setup disk.
Hi Aiden,
Please run:
bcdboot C:\Windows
mbr2gpt /validate /disk:1 /allowfullOS
Post the output.