Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.

Windows 7: windows 7 boot loader missing/corrupt

01 Nov 2010   #1

Windows 7 Ultimate x64
windows 7 boot loader missing/corrupt

I recently Uninstalled my Ubuntu 9.10 partition from my 500gb IDE hard drive, and thought nothing of formatting the partition and setting it up as a new windows drive.
But, out of my own forgetfulness, i forgot that in rder to dual boot windows 7 with ubuntu, you Have to install the GRUB boot loader to be able to boot into both at will. this process wipes the original windows bootloader, and simply replaces it. Well, once I rebooted my pc, GRUB attempted to find a linux partition that was not there, and gave me this: "Error:unknown filesystem. Grub rescue>"
After some online digging, I found several articles that told me to use the "repair" feature on the windows 7 install disc. I did this, and the Disc was unable to find my windows 7 installation, although when i used the x:/ command prompt, i was able to easily see the C: drive,and the windows system. When i used the "repair startup" command, it ran through and told me that it was unable to fix the error, and that the root was that the Bootloader was missing or corrupt.
I think this is an error caused by what i think to be the real root dilemma, when my hard drive is physically set as the first boot device, the CD-rom drive is undetected by the BIOS, and vis versa, although when the CD-rom is set as the first, im able to boot into the windows 7 install CD. Im not sure if this is due to my BIOS being outdated, or what could cause this-but i believe its causing the cd to not see the drive as a boot device, or a win-7 installation.
Any help would be greatly appreciated, I have scoured these forums, and worked for hours on my own to no avail.
all suggestions are appreciated.
Thank you for reading this small book i seem to have typed.

My System SpecsSystem Spec
01 Nov 2010   #2

Microsoft Community Contributor Award Recipient

Windows 10, Home Clean Install

Is this what you are missing?
MBR - Restore Windows 7 Master Boot Record
My System SpecsSystem Spec
02 Nov 2010   #3
Bare Foot Kid
Microsoft MVP

W 7 64-bit Ultimate

Hello chbell10, welcome to Seven Forums!

You can see an out-line of the partition specific wipe process at Option Three of this tutorial at the link below; there is also additional useful information at the second link and be sure to post back with any further questions you may have and to keep us informed.

Partition Wizard : Use the Bootable CD

Startup Repair - Run 3 Separate Times
My System SpecsSystem Spec

02 Nov 2010   #4

Windows 7 Ultimate x64

I tried all of the solutions listed above, and again to no avail. I wiped the Drive which previously had grub on it with the bootable CD, and marked the windows 7 drive as active, and that did nothing for the repair tools to see the installation, although when i followed the link provided by Richc46, it showed that there was indeed a win 7 ultimate installation in place, alas when i ran the command "bootrec /rebuildbcd", it told me that "the requested system device cannot be found".I also ran the repair 3 times with reboots, but that only gave me the new root error "NoOsinstalled", which is very contradictory of it to say,I think -_____-
I forgot to mention before, but this might be of some help, when at the basic first screen of the windows 7 DVD,
I select "repair my computer", It proceeds to a progress bar window, which says on it "searching for windows installations", which then proceeds to a dialogue boxt stating "windows found problems with your computers startup options. Do you want to apply repairs and restart your computer?", and i then select "repair and restart", which promptly gives me an error dialogue box saying "failed to save startup options", which then proceeds to the section where you choose your windows installation, but in my case-it shows nothing at all.
Maybe that will help a diagnosis.
Thank you for your help, and time(:
My System SpecsSystem Spec
02 Nov 2010   #5
Microsoft MVP


Boot the Win7 DVD, press Shift F10 to open a Command Line, type:

bootrec.exe /fixmbr
bootrec.exe /fixboot

Close command line, enter Repair console to see if it now finds an installation to repair and will Startup Repair correctly.

What you are doing here is jump-starting the Repair by preceding it with bootrec commands which are automated in Win7 Startup Repair, but which may not be completing if it is malfunctioning due to OS corruption.

In the future, consider putting Linux distribs on a separate HD booted via BIOS so that GRUB is not necessary and Win7 isn't involved. Backup a Win7 image externally so that you never have to reinstall again.
My System SpecsSystem Spec
02 Nov 2010   #6

Windows 7 professional x86/

Firstly - I have removed grub with the simple bootec.exe /fixmbr 100% of the time.

So from the top - make sure SATA native mode is disabled in your BIOS (device config)

Installation DVD - R - Command

bootrec.exe /fixmbr
bootrec.exe /fixboot

bcdedit /export C:\BCD_Backup
cd boot
attrib bcd -s -h -r
ren c:\boot\bcd bcd.old
bootrec /RebuildBcd
My System SpecsSystem Spec
02 Nov 2010   #7

Windows 7 Ultimate x64

I tried your suggestions, but There was no change in the repair error. It says that "startup repair cannot automatically repair this computer"

Would any other information be helpful in any way to solving this?
if so, please let me know, and I'll do my best to oblige.
My System SpecsSystem Spec
02 Nov 2010   #8

Windows 7 Ultimate x64

And to solarwind, This is the error i got when i used the command listed:
"bcdedit /export C:\BCD_Backup"-The store export operation has failed. The requested system device cannot be found.
My System SpecsSystem Spec
02 Nov 2010   #9

Windows 7 professional x86/

This is quite a problem! :)

Tak a look at the following: Windows 7 Suddenly Won’t Boot – Reboot and Select Proper Boot Device or Insert Boot Media in Selected Boot Device and Press Any Key – Repairing the Windows 7 Bootloader Russ' Do It Yourself Home Workshop

Follow the instructions from where it says additional actions i.e DISKPARTand fingers crossed this solves it. Other than that I am totally out of ideas so could only recommend a complete reinstall.

My System SpecsSystem Spec
02 Nov 2010   #10
Microsoft MVP


All of those bootrec and bootsect commands are automated in Win7 Startup Repair, along with dozens of other tests and fixes which require it sometimes to be run up to 3 separate times with reboots to complete MBR repairs.

However, as implied earlier bootrec can sometimes jumpstart the Repair utility if no installation is found to begin with.

Some installations cannot be repaired, especially ones corrupted by GRUB. I will often go on running Startup Repair anyway and sometimes get it running but at some point you may want to cut your losses, wipe your HD and clean reinstall the OS's to separate drives if at all possible. If not: Where to install ubuntu in my system?

You can copy out your files if necessary using the DVD with this method: Copy & Paste - in Windows Recovery Console
My System SpecsSystem Spec

 windows 7 boot loader missing/corrupt

Thread Tools

Similar help and support threads
Thread Forum
Corrupt or Missing BIOS - no POST, can't boot from USB or CD
Dell Optiplex 790 (SFF). Will not boot - Diagnostics are Amber Power light (steady) and diagnostic lights 2,3 & 4 flashing amber - this indicates a corrupt or missing BIOS. Turning on, the PC powers up but immediately starts the flashing diagnostic lights. This is my daughters computer and appears...
General Discussion
BSOD then no boot cause fwpkclnt.sys is missing or corrupt
I got a BSOD on my SSD and booting up it told me that "fwpkclnt.sys is missing or corrupt". I ran Startup Repair, tried System Restore, did a few things in command prompt, and nothing has worked. So I switched to my HDD for a day (it was working fine) but then overnight it BSODed or something and...
BSOD Help and Support
BIOS Update - Boot Loader Missing
I am for sure gonna get kicked out of this forum for being so annoying. I hope not, because some of the smartest people I have found are in this great forum. Anyway, I did something I know was newbie-stupid wrong. I tried the ASUS EZ Update from within Win 7 to update my ASUS Crosshair V Formula...
Hardware & Devices
Issues with recovery and missing boot loader
Ok, I read over this forum, and tried several of the options. My issue: Boot loader is missing from HD. I entered the windows repair from dvd, and it finally showed the windows installation, C:\Windows (recovered). Tried selecting it again to have windows reinstall MBR, but now it says...
Installation & Setup
Win 7 boot files missing or corrupt
I have an Advent Roma 2001 configured, in PC World style, with a "recovery partition" alongside the system partition and, after resolving a hard disk problem, I found that the machine would not start/boot Windows 7. clearly some necessary files are missing or corrupted, but the normal system...
Performance & Maintenance

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 07:03.
Twitter Facebook Google+