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NVIDIA drivers upgrade crashed my Windows 7 installation, so I'm working to undo the damage.

What I can do: I can boot Windows install from the USB drive, and I can boot the Hiren's Boot CD. Although automated Windows repair fails, I can get to command prompt when I boot Windows install from USB drive, and I can see my drive and all my data.

What I cannot do: I cannot boot into Windows - I get this message:

Windows failed to start. A recent hardware or software change might be the cause. To fix the problem:
1. Insert Windows CD and run a repair your computer option.
File: /Boot/BCD
Status: 0xc000000f
Info: an error occurred while attempting to read the boot configuration data.

It seems that something is wrong with my /Boot/BCD, so I'm trying to recreate it from scratch. I've tried all the methods detailed here (including Windows repair which fails), and I'm left with the last one (near the bottom of that page). When I type the following command as in the tutorial:

bcdedit.exe /import c:\boot\bcd.temp

...it fails with the following error:

The store import operation has failed.
The requested system device cannot be found.

Many Google results say that I must use diskpart to set my partition active, however it's already set as active.

Also, when I try this:

bcdedit /enum

It fails with similar message:

The boot configuration data store could not be opened.
The requested system device cannot be found.

Does anyone know what does that error message mean, and what is the requested system device?

I'd like to avoid having to reinstall Windows since all the files on disk seem to be fine.

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Did you try the "bootrec /RebuildBcd" command? (no quotes) –  Moab Jun 27 '11 at 4:23
Yes, it lets me choose my Windows installation, but when I do it fails with "The requestted system device cannot be found." –  Domchi Jun 27 '11 at 5:14
Please type just bcdedit and post the response. –  Sean Jun 27 '11 at 7:59
Windows 7 by default doesn't store the BCD or the boot information on the C: partition, it stores it on a 100MB partition and this partition needs to be active, not the C: –  Sean Jun 27 '11 at 8:04
Sean, I get the same error message when I type bcdedit as I get when I type bcdedit /enum, please see above. –  Domchi Jun 27 '11 at 8:27

6 Answers 6

I've found in situations like these, that "EasyBCD" is really really helpful. I suggest you give that a whirl and see if it can't save ya.

Hope that helps dude. Cheers!

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I'd like to, but to run EasyBCD I need bootable Windows 7. Which I don't have. The tutorial to regenerate BCD I'm working with above, and which I can't follow through, is actually from EasyBCD website. Can EasyBCD be run from Windows repair console, or from Linux...? –  Domchi Jun 27 '11 at 3:45
Can't install it on Windows XP which comes with Hiren's Boot CD, install fails when it's supposed to install .NET and cancells itself automatically. But even if I installed it, WinXP doesn't see NTFS disk with BCD... –  Domchi Jun 27 '11 at 5:32
At the end, I managed to install EasyBCD on the other machine, and have it chew on my BCD file which I copied there. But I never managed to do anything useful with it... –  Domchi Jul 9 '11 at 23:02

Boot a Windows 7 x64 install disc and launch Start Up repair, but cancel it before it starts trying to repair, you will see a link for Advanced Options, which will allow you to get to command prompt, you will need to make the 100MB partition active if you made the OS partition active by mistake.

  1. Put the Windows 7 x64 installation disc in the disc drive, and then start the computer.
  2. Press a key when you are prompted.
  3. Select a language, a time, a currency, a keyboard or an input method, and then click Next.
  4. Click Repair your computer.
  5. Click the operating system that you want to repair, and then click Next.
  6. In the System Recovery Options dialog box, click Command Prompt.

    diskpart select disk 0 select part 1 active

Reboot and boot back into the Windows 7 x64 install disc.

bcdedit /export C:\BCD_Backup
cd boot
attrib bcd -s -h -r
ren c:\boot\bcd bcd.old
bootrec /RebuildBcd


share|improve this answer
On step 5. I don't have any operating systems listed. I don't have 100MB partition, never had, and my partition is already active, as I said in my question. I tried all that KB you mention suggests, but bootrec /RebuildBcd fails with "The requested system device cannot be found." –  Domchi Jun 27 '11 at 8:34
sounds like maybe a bad hard drive or corrupted file system. Run chkdsk /r You can also test the hard drive using a Linux live disc like PartedMagic partedmagic.com, which has a tool called GSmartControl for checking hard drives for errors and running S.M.A.R.T tests. It also contains a tool call testdisk, which can be used to try and repair the file system cgsecurity.org/wiki/TestDisk –  Sean Jun 27 '11 at 9:04
Hard drive and file system are OK - I can see all the data from PartedMagic linux environment. Also, TestDisk was what I previously used to fix MBR. Before I used TestDisk, I wasn't even able to access the partition. My problem is definitely the incorrect BCD file, and I would really like to know why I can't recreate it and what is that requested system device he can't find. –  Domchi Jun 27 '11 at 16:44
up vote 10 down vote accepted

So, here's how I finally solved it.

Recreating BCD as in the "nuclear holocaust" chapter of the tutorial I mentioned in my question worked in the end, but with one small modification. I got the idea in this thread. It seems that the message I got was telling me that bcdedit cannot find the BCD store. So, instead of typing this:

bcdedit /import c:\boot\bcd.temp

...I only needed to manually point to the store:

bcdedit /store c:\Boot\BCD /import c:\boot\bcd.temp

This is also needed for the rest of commands in tutorial:

bcdedit /store c:\Boot\BCD <the rest of the command>

With that modification, all the commands in tutorial work as expected. When I recreated BCD, I was able to boot my original Windows.

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That's very strange, since bcdedit /? store says This option may not be used with the /createstore, /import, or /export commands. Trying to use it anyway results in The store import command is invalid. Glad it worked for you. –  Dave Jul 1 '13 at 0:32
Same error here... Has anyone got a clue? –  ChaotiCc Nov 5 '13 at 0:34

Not directly related to your issue as you resolved it, but rather to your original description (particularly "The requested system device cannot be found." on BCD operations despite all attempts to recreate/rebuild):

This error can happen if you are booting from a USB stick, and your BIOS supports a given usb slot, but the windows PE/repair environment does not!

I spent two days pulling my hair out, wrestling with this issue (the BCD store was ALWAYS unavailable with this "The requested system device cannot be found." error, no matter what I did), only to find that the problem was simply the USB slot I was plugging my bootable USB stick in. By plugging it into a different (usb 2.0 instead of usb 3.0) slot, the standard repair actions worked fine.

To make matters worse, I later discovered that it was by plugging in the wrong slot and allowing the rescue environment to attempt auto-repair that I messed things up in the first place!

Update: Another user (improvedcomputers) contacted me to confirm that this also happened to them; as all their USB slots were unrecognized by Windows 7 PE they ended up having to pull the drive and perform the repair on another computer.

Update: I had hard time even reinstalling windows on my laptop. From this post I learned and realized the Windows 7 PE does not recognize USB drive. Although it booted from the USB drive image due to some reason it was not able to start up the installation process. After whole day of efforts finally I tried it with DVD and it worked. I am using Lenovo W520

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After just spending 3 hours trying to debug that error message, I can't thank you enough. Seriously, thank you! I never would've imagined that using a USB3 slot would've been causing that. –  Corbin Nov 24 '12 at 2:30
+1 Wow, same here! Just saved my life after a repartition gone bad. –  mellamokb Dec 21 '12 at 7:14
I am exceedingly glad now that I have 2 usb2.0 drives. I was initially annoyed at them (preferring all usb3s), but now I realize how useful they are. I was wondering why my mouse wasn't working during recovery. That should've tipped me off that it wasn't recognizing 3.0 ports for some reason. –  saccharine Oct 20 '13 at 11:23
thanks! this just fixed my frustrating attempt to use bootrec to fix a cloned drive. Pop win7 recover USB stick in another slot and you're set to go lol –  Michael Nielsen Mar 29 '14 at 18:36
Amazing... I too have a Lenovo W520 and after a power outage and Windows trying to do startup repair I was in the same situation. I successfully got into the repair environment but I was getting "Element not found" errors when trying to use bootrec /fixboot and the Startup Repair itself was never having any success. Of course it turns out that using a USB stick was the culprit. Switching to an old Windows 7 CD did the trick and I didn't even need to run any of those commands. Startup Repair ran twice and then successfully fixed things. –  Kevin Morse Jul 19 '14 at 7:57

I had a different cause of and solution to this issue. In my case the problem was that I had used a Windows 7 Enterprise ISO to create a bootable usb flash drive with Unetbootin, per instructions here: http://www.webupd8.org/2010/10/create-bootable-windows-7-usb-drive.html. Basically, the instructions say to format the usb drive with ntfs and use Unetbootin v494 (outdated) which still had the feature to allow you to use drives formatted with ntfs (this feature disappeared in later versions).

Something tingly in the back of my head told me that non-standard procedure was going to cause headache, but I ignored it.

After an hour of forum searching, someone somewhere mentioned "don't use a bootable usb drive as the recovery environment will see that partition table and not the real one on the hard drive," or something to that effect.

Found my USB CD-ROM drive, put the real disk in there, and ran bootrec /fixmbr, bootrec /fixboot, and bootrec /rebuildbcd with no issues. Windows then started fine, both from grub and when the secondary hard-drive was chosen from the bios boot list.

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The requested system device cannot be found.

I had the same error message when I was trying to repair windows after converting my hard drive from MBR to GPT. When I tried automatic repair, windows even reported the installed version was not a compatible windows version. I found out that the MSI bios had two options for booting from DVD-ROM which looked similar to this:


It would only start the UEFI boot when I manually selected it. Otherwise it would still boot from the DVD-ROM but not in UEFI mode. After I selected UEFI, I could both manually and automatically repair my windows 7 system.

I have now completely disabled to boot from CD/DVD, forcing me to use the bios boot-menu and choose how to boot.

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protected by nhinkle Jun 27 '11 at 5:04

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