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My whole question is in the title. Is it possible to repair Windows 10 BCD using another version of Windows installation disk, Windows 7 in this case? I got the Windows 10 BCD corrupted when I installed RemixOS on a separate partition that I created from an existing free space while booting from the RemixOS installation media.

If this is not possible, what are the alternatives, other than downloading Windows 10 ISO file and creating an installation media for windows 10? I have Kali Linux and Elementary OS installed and I can boot into them. I also have Remix OS installed and running fine. I can install Wine if it is possible to fix the Windows 10 BCD using some Windows application that can allow me to select the BCD file that I would like to fix or something similar.

Supreme Dolphin
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2 Answers2

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You can boot Windows 7 installation USB/DVD.

Go to recovery console.

Run bcdboot.exe from Windows 7 and see if it can fix BCD - format of BCD objects and elements has not changed since Vista.

bcdboot W:\windows

where W: is Win 10 partition, change drive_letter to your mapping.

There are more parameters which you can use when executing the bcdboot command - see Repair Windows BCD for explanations.

EDIT:

As it come out that Windows 10 is on GPT disk it is better to use this:

bcdboot c:\windows /s d: /f UEFI /l en-us

Notes:

  1. You have to boot Windows 7 DVD/USB the UEFI way.

  2. You should map EFI System partition to drive letter d: (or another)

  3. Use language code with parameter /l which is the same as Windows 10 installation language.

If this does not help you can create manually a Windows 7/8/10 loader using bcdedit.exe command: (assuming Windows 10 is on c: and EFI System on GPT is mapped to S:)

bcdedit /store S:\EFI\Microsoft\Boot\BCD /create /d "Windows 10" /application osloader

The command creates a loader object and outputs its GUID. Copy this GUID as you will need it in next command.

bcdedit /store S:\EFI\Microsoft\Boot\BCD /default {GUID}

This sets the default boot entry to Windows 10.

bcdedit /store S:\EFI\Microsoft\Boot\BCD /set {default} device partition=c:
bcdedit /store S:\EFI\Microsoft\Boot\BCD /set {default} path \windows\system32\boot\winload.exe
bcdedit /store S:\EFI\Microsoft\Boot\BCD /set {default} osdevice partition=c:
bcdedit /store S:\EFI\Microsoft\Boot\BCD /set {default} systemroot \Windows
snayob
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  • How do I open the Recovery Console? When I click on Repair at the bottom left of the screen, I get an error that the recoveey options is incompatible with the version of Windows... When I close the pop-up window, it takes me back to the installation page and that's it. – Supreme Dolphin Mar 06 '17 at 06:20
  • You can use "Shift+F10" on language selection screen and you get command prompt. – snayob Mar 08 '17 at 02:45
  • Okay I did that. The bcdboot C:\Windows command raised an error at first. So I gave the System partition a letter S and then did bcdboot C:\Windows /s S: and that completes successfully. However, I wasn't able to boot. I also tried the /s C: and /s H: where H: is the recovery partition. Still couldn't boot. When I updated grub from Linux, the "Windows Recovery Environment" entry was gone. Instead, there were three entries all "Windows 10." Bootrec /RebuildBcd fails with an error that "required system device could not be found." I'm at a dead end now. – Supreme Dolphin Mar 08 '17 at 06:01
  • Is Windows 10 on GPT disk or MBR disk? – snayob Mar 09 '17 at 04:07
  • Windows 10 is on GPT disk. – Supreme Dolphin Mar 09 '17 at 08:14
  • Try suggested and extended bcdboot command and eventually manual loader creation. – snayob Mar 12 '17 at 04:52
  • Be advised that the bcdboot.exe from Windows 7 (or BCDBoot Version 6.1.7601 & earlier) does not recognize /f option, nor does it supports UEFI. You need at least a Windows 8 installation disc. – iBug Mar 12 '17 at 05:22
  • @iBug, where have you seen that bcdboot on Windows 7 does not support UEFI? Do you have a reference from Microsoft or another reliable site? – snayob Mar 12 '17 at 06:53
  • AFAIK Windows 7 supports UEFI. I have Windows 7 installed on GPT disk and booting from it without any problem. It is hard to believe that a Microsoft system tool for repairing/fixing BCD on Windows 7 does not know about UEFI. – snayob Mar 12 '17 at 06:56
  • @syanob I'm not sure if there are multiple versions of bcdboot from Windows 7, but the one that comes with the OS does not recognize /f. Maybe the ones from WinRE environment and Windows 7 AIK is slightly different. – iBug Mar 12 '17 at 15:34
  • iBug is right. The /f is indeed missing from the Windows 7 disk. I tried the second option, which completed successfully, but of course with a few modifications since the system does not use UEFI boot even though it's on GPT disk. The difference with the edit is that the /store was S:\BOOT\BCD. I named the entry Windows 10 Edited. However, when I updated grub, it didn't show. Rebooting Windows confirmed that nothing had changed. – Supreme Dolphin Mar 12 '17 at 16:50
  • I am confused. Is the disk GPT style or MBR style? There are some differences how Windows boot from GPT disk and from MBR disk. Is the firmware BIOS or UEFI? Is CSM enabled if firmware is UEFI? – snayob Mar 14 '17 at 05:55
  • Post the output of diskpart command - "list disk". Also output of "select disk 0" - "list part" (while in diskpart). You can "quit" or "exit" diskpart when finished. – snayob Mar 14 '17 at 05:57
  • Great answer! Add some info on restoring for BIOS as well and it will be even better. – hypers Sep 28 '18 at 20:25
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I did once use Windows 7's automated repair to fix a Windows 10's BCD and it worked. Nevertheless, it is possible that your type of damage is different from mine. Is it really BCD that is hurt?

On Linux, you can use Boot-Repair to repair the Windows boot process. But again, it depends on what kind of damage you are talking about.

From another copy of Windows, you can run Bootice.

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    I'm sure it's a BCD issue. When I try to boot into Windows 10, it gives the error code 0xc000000e and and gives the file \BOOT\BCD. I will try your methods. – Supreme Dolphin Mar 04 '17 at 11:57
  • The Windows 7 gives an error that the "Recovery Options is incompatible with the version of Windows" I'm trying to repair. I'll try the Linux options. – Supreme Dolphin Mar 04 '17 at 12:27
  • Boot-Repair-Disk didn't help. – Supreme Dolphin Mar 04 '17 at 13:27
  • Your last shot seems to be Bootice then. Meanwhile, I am trying to confirm whether the "Recovery Options is incompatible with the version of Windows" message is because of your damaged condition or is something normal. –  Mar 04 '17 at 13:30
  • Alright. But in order to use Bootice, I need to install Windows 7 on a separate partition and run it? Or is it something I can do on Wine from Linux? – Supreme Dolphin Mar 04 '17 at 13:33
  • I have zero experience with Wine. But you said you have a Windows 7 installation disc. Maybe you can boot into it and run Bootice from its command prompt. Try it. –  Mar 04 '17 at 13:38
  • Is it possible to boot into Windows 7 without installing it? Wine is a Linux program that allows one to run Windows applications and games in the native environment. If Bootice is just a normal exe, I guess it should work. – Supreme Dolphin Mar 04 '17 at 13:40
  • The Windows Setup itself is a Windows 7. You said you tried repairing your BCD from it. That means you have opened its recovery tools and so you know how to go there. One of the tools available there is a Command Prompt. You can use it to run Bootice from a flash drive. –  Mar 04 '17 at 13:45
  • I reached there alright. I clicked "repair" but didn't go past. I only got a pop-up window with the error message. I didn't get to any command prompt whatsoever. If Bootice is something that can help, then I think I'm going to go for it. I'll just install Windows 7 and run it from there. – Supreme Dolphin Mar 04 '17 at 13:55
  • Great answer! Add some info on restoring for BIOS as well and it will be even better. – hypers Sep 28 '18 at 20:24