Bootcamp installation completely messed up, unusable

Thanks Loner T. Those commands executed successfully. I've attached a photo of the output of bcdedit after those.

Tried to boot back into Windows and still seeing the odd two Windows partitions in option-boot (I think they both point to the same partition) and still getting "Error code 0xc0000225, 'required device missing'" message on the first try and "The application or OS couldn't be loaded because a required file is missing or contains errors." pointing to \Windows\system32\winload.efi." when I push Enter to try again.

I booted back into the recovery section of my Windows USB installer and when I run bcdedit in Command Prompt, I get this error message:

"The boot configuration data store could not be opened. The requested system device cannot be identified due to multiple indistinguishable devices potentially matching the identification criteria."

Poking around online, I see that this can happen when it sees multiple EFI partitions, which I indeed confirmed through diskpart. I found this link – Issue with a Windows 7 Boot issue - involving the BCD perhaps - Super User– but I'm not quite following.

Can you please walk me through the commands I would use here? I've attached some diskpart output that I was using as reference. My iMac has a Fusion Drive, and WINREC is the USB drive I'm booted off of.

Once that is taken care of, am I understanding you correctly in that I would then want both the Boot Manager and Boot Loader sections' Device field to say partition=\Device\HarddiskVolumeN, where N is the same for both and is the volume of the EFI we are left with after solving the aforementioned issue?

I really appreciate your patience and guidance in this issue and you are being a massive help, just as you have been to so many others. Thank you so much for helping me out here in these frustratingly cascading issues.

Hi Loner T,

Thanks for your guidance.

As a reference, please note that referencing the screenshot in my post above, Volume 1 was assigned R: and Volume 2 was assigned S: using Diskpart.

It appears that I have two EFI/Microsoft partitions!

I poked around a bit and it appears that R: has a Boot/BCD and S: has the Boot/BCD that I originally tampered with, that I renamed to BCDOLDER while I copied the clean one from the installation media (as I mentioned in my very first post, probably the cause of all this).

How would you proceed from here? I would imagine that mounting that EFI and putting BCDOLDER back probably won't help much. Additionally, it seems like we have to eliminate or at least force Windows to use only one of these EFI partitions. This would also explain why I get two Windows partitions showing when I hold option and boot.

Thanks again!

Hi Loner T,

To remove the MBR, do I use these commands that I found in another post of yours?

sudo gdisk /dev/disk0

x (experts menu)

n (create a new protective MBR and remove the Hybrid MBR)

o (print the new MBR)

p (print the partition table)

w (write)

y (confirm write)

Thanks for offering your assistance. I will post the output of bcdedit when I get home.

Thanks for the link.

Attempted to run:

bcdedit /store C:\Boot\BCD /enum

bcdedit /store C:\Boot\BCD /set {default} device partition=C:

bcdedit /store C:\Boot\BCD /set {default} osdevice partition=C:

However, any of these commands give me:

"The boot configuration data store could not be opened.

The system cannot find the file specified."

Attempted to run

bcdboot S:\EFI\Microsoft\Boot

Consistently getting "failure when attempting to copy boot files".

Thanks again for your help. If you feel this is a lost cause, let me know, this windows partition is not critical but it would really be nice to have with all my games.

I performed those commands as written.

Here is the output of bcdedit from the Command Prompt accessed from my Windows 10 USB repair screen.

Thanks!