Windows 11 Update 25H2 Error and WinRE Problems

In this comment - it seems like that should be part 4, not part 1 - since part 1 is the main OS partition.

diskpart
select disk 1
select part 1
set id=c12a7328-f81f-11d2-ba4b-00a0c93ec93b override
gpt attributes=0x8000000000000000
assign letter=Y
list part
list vol
exit
bcdboot c:\windows /s Y:

Please post the latest Disk Management screenshot.

I did create the FAT32 partition - which ended up being 99MB. It's in the first slot in disk management, but listed as part 4 in diskpart:

Gotcha. Maybe it's a good idea to post a screenshot of Disk Management after a reboot.

Edit: By "Gotcha", I meant "I understand". It can sometimes convey a different meaning.

The next steps will be:

To create the EFI partition

Remove the EFI partition located at the end of the drive.

Remove the boot folder in the C drive. This has to be done via WinRE (USB boot).

Once done, enable WinRE.

boot.txt

After a restart, it was part 1. Followed the commands above

The commands ran fine.

Can you open msinfo32.exe and check the boot mode?

It should read UEFI.

Run:

diskpart
disk 1
select part 4
set id=ebd0a0a2-b9e5-4433-87c0-68b6b72699c7
gpt attributes=0x0000000000000000
exit

Now, you should be able to delete the EFI partition at the end of Disk 1. Please do so.

Sorry - yes, it's UEFI:

Partition deleted

Great. Please boot into WinRE using the USB disk.

In WinRE Command Prompt, run:

bcdedit | find "osdevice"

In the output, note the drive letter for the OS partition.

Suppose it's D:\

Run:

attrib -s -h -r D:\EFI

ren D:\EFI D:\Unused.EFI

wpeutil reboot

(If you get any errors, please mention them here.)

Boot into Windows and post the latest Disk Management screenshot.

I'm getting this when running bcdedit from the command line:
The boot configuration data store could not be opened.

The requested system device cannot be found.

Though checking the volumes, it is assigned D:

Let's see if the drive letter Y is intact.

Run:

diskpart
list vol
exit

Run:

select volume 2
assign letter=y
list vol
exit
bcdboot d:\windows /s Y: /f ALL
dir Y:\BCD /s /a

Let's rename the EFI folder on the OS drive. (If Windows doesn't boot, we may need to revert the change later.)

Run:

attrib -s -h -r D:\EFI

attrib -s -h -r D:\Boot

ren D:\EFI Unused.EFI

ren D:\Boot Unused.Boot

wpeutil reboot

(If you get any errors, please mention them here.)

Boot into Windows and post the latest Disk Management screenshot.

I've modified the 3rd command. Please refresh this page.

Very good.

Please run:

bcdedit 

reagentc /disable

reagentc /enable

reagentc /info

Lovely!

Great. WinRE is sorted. Unfortunately, I skipped checking the Disk Management screenshot (in your original post) earlier. Only noticed the problem in the full Disk Management screenshot posted today.

If you want to merge the free space next to the Recovery partition, let me know.

If this also fixes the 0xC1900101 error, that will be great.

I'll be able to handle merging the unused space back in myself - have recreated the recovery partition before, so I'm not too worried about that (and it's only a few hundred megs anyway).

I'll test updating again tomorrow - hopefully this has fixed the issue. Thanks for all your help so far!

Good luck and keep me posted.

Thanks for all your help so far!

You're welcome.

Updated this morning, and everything went smoothly. Looks like the WinRE issue was the culprit in this case.

Thanks for your help!

Run:

select disk 1
list part
exit

Run:

bcdboot d:\windows /s Y:
diskpart
select disk 1
select part 4
del part override
select volume Y
remove
exit

Note: It appears you didn't exit from diskpart. Please exit diskpart before running the latest commands.