How can I rebuild the Windows boot files?

After a virus, the boot files on a Windows 7 computer are gone, and I get this message when booting...

File: \Boot\BCD
Status: 0xc0000000f
Info: An error occurred while attempting to read the boot configuration data.

So I booted from my Windows 7 USB thumb drive and opened the command prompt. I mounted the drive with the OS install to the L: using diskpart, and then I changed to the L: drive then typed the following

L:\>bootrec /fixmbr
Command completed succesfully
L:\>bootrec /fixboot
Command completed succesfully
L:\>bootrec /rebuildbcd

I say I want to add the Windows install on L: so I type Y hit Enter and I get The requested system device cannot be found.

So how do I rebuild the Windows boot files; why can't the system device be found?

Below is a log of the commands I run as well as the windows usb install drives' attempt to repair it

When I click repair computer Windows scans for Windows Installs and then pops up this dialog

[[System Recovery Options]] <-- Title

Text is.... (no '-' though) -------------- Windows found problems with your computer's startup options. Do yo want to apply reparis and restart your computer?

View deatails

Then the buttons

[Repair and restart] [No]

When I click View details I get another dialog

[[Systen Recovery Options]]

Repair details: (then a scroll box with the deatils) The following startup option will be repaired: Name: {bootmgr} Identifier: {9DEA862C-5CDD-4E70-ACC1-F32B344D4795}

The following startup options will be added: Name: Windows 7 Home Premium (recovered) Path: Windows Windows Device: Partition=D: (595364 MB)

Name: Windows Recovery Environment (recovered) Path: Recovery\WindowsRE\Winre.wim Windows Device: Partition=C: (15000 MB)

A copy of the current boot configuration data will be saved as: C:\Boot\BCD.Backup.0002

[Close]

So I click Repair and restart and get

A error dialog that says [[System REcovery Options]]

X Failed to save startup options

[Ok]

So I click Ok

and get the normal windows that allows you to retore from an image or try and use recovery tools

Selected either options and clicking next gives me a dialog to Choose a recovery tool and buttons at the buttom to shutdwon or restart

So I open cmd and type the following

Microsoft Windows [Version 6.1.7600]

X:\Sources>diskpart

Microsoft DiskPart version 6.1.7600 Copyright (C) 1999-2008 Microsoft Corporation. On computer: MININT-8COAH39

DISKPART> list volume

Volume ### Ltr Label Fs Type Size Status
Info ---------- --- ----------- ----- ---------- ------- --------- -------- Volume 0 E DVD-ROM 0 B No Media Volume 1 C Recovery NTFS Partition 14 GB Healthy Volume 2 D OS NTFS Partition 581 GB Healthy Volume 3 F Removable 0 B No Media Volume 4 DELLUTILITY FAT Partition 100 MB Healthy Hidden

DISKPART> select volume 2

Volume 2 is the selected volume.

DISKPART> assign letter = l

DiskPart successfully assigned the drive letter or mount point.

DISKPART> exit

Leaving DiskPart...

X:\Sources>L:

L:>bootrec /fixmbr The operation completed successfully.

L:>bootrec /fixboot The operation completed successfully.

L:>bootrec /rebuildbcd Scanning all disks for Windows installations.

Please wait, since this may take a while...

Successfully scanned Windows installations. Total identified Windows installations: 1 [1] L:\Windows Add installation to boot list? Yes(Y)/No(N)/All(A):Y The requested system device cannot be found.

L:>bcedit 'bcedit' is not recognized as an internal or external command, operable program or batch file.

L:>

Try these general steps:

• Make another install of windows on the same disk on the same computer in a different partition. (Shrink your Windows partition and make a 30GB one, then install 7 in that.)
• Copy all of your boot files from the new install to the broken one using a Linux LiveCD (I would recommend Ubuntu as it comes with GParted, software which will allow you to do the aforementioned partitioning changes)
• Select your old 7 install from the boot menu and see if it works. If it does, delete the new partition and run startup repair.
• If it doesn't doesn't, consider using a Linux LiveCD (I prefer Ubuntu, a very user-friendly distro) to copy your data over to a new install of Windows, either disk-to-external-media-and-back-to-disk or just into a new Windows partition.

I have had the same problem... after two days of various trials, I tried:

bcdboot c:\windows

But it did not work for me so I tried:

bcdboot c:\windows /s c:

And all boot files were copied and the system is back online.

Assuming that c: is your system drive, and Windows is installed to the \Windows subdirectory, try running:

bcdboot c:\windows