At the beginning I have been Windows 7 on /dev/sda1. After that I have installed Ubuntu in /dev/sda7 and set Grub partition to /dev/sda1. Which broked down Windows 7 boot. Ubuntu have booted normally from Grub Menu, but when I choosed Windows 7, grub disappared and after 1 second appeared, and doesn't load. After that I have searched for some fixes for Windows 7 boot, and I do some "fixings". The result - Grub doesn't load.

At this moment I have broken Windows 7 loader and broken Grub. And sitting with Ubuntu Live CD. How can I fix this with Ubuntu live CD? If possible please give step by step explanation, because I newbie in Ubuntu and Linux.

EDIT: Grub loader fixed. But anyway... Windows 7 doesn't load from Grub. I'm using Grub2.

EDIT2 As I understand I need to run bootrec.exe /fixboot to fix Windows 7 bootloader. But I don't have Win7 DVD at this moment. Any way to do same from Ubuntu?

EDIT3 Boot Info Script RESULTS.txt is here: http://pastebin.com/Z70fKQHJ


There is no way to fix the windows 7 bootstrap from Ubuntu, you will need to do so with the windows 7 DVD but, which size is sda1, if it is +/- 100Mb, you should not have much troubles fixing it but, will need to reinstall grub to another partition. If it is way bigger than 100Mb, this mean it was not the system reserved space and that you have installed Grub over your windows 7 thus, deleting windows 7 completly....

  • I have changed grub partition to /dev/sda. So at this point, I need to only do bootrec.exe /fixboot? – Toktik Dec 15 '10 at 3:14
  • yes, unless you had put Grub over Win7. Once your win7 boot is restored, you may need to log again with the ubuntu live disk, go in a terminal and type "sudo grub-update" so it points the items (ubuntu and win7) to the proper partition – Mobidoy Dec 15 '10 at 3:28
  • 1
    Toktik most likely did overwrite the Windows partition boot record on /sda1 when he installed Grub2 there. – Takkat Dec 15 '10 at 20:55

I had same issue. After trying other solutions on the internet, I ran from Ubuntu terminal:

> sudo update-grub

It located the Windows and Ubuntu installations automatically fixing the boot issues.

Hope this helps someone.

  • This worked for me today. Fixed grub using the amazing Rescatux (supergrubdisk.org/rescatux), then ran update-grub and all is well in my dual-boot world. – udog Jul 14 '13 at 4:15
  • Here is a link for a recovery ISO,download and burn it into a cd.
  • Boot with your Windows 7 recovery disk.
  • Hit Enter at the language selection prompt and then hit R for Repair to get to the Repair section.
  • Select the command prompt and type in the following command

    bootrec.exe /fixmbr

  • The proposed solution links to a PAID download. There are links on the internet to download full Windows 7 installation images (containing recovery) from DigitalRiver without paying a cent ! – snayob Jul 24 '12 at 3:20

From your Bootinfo script we can see that your partitions are inconsistent somehow:

Grub 2 is installed in the MBR of /dev/sda and looks at sector 505377176
of the same hard drive for core.img, but core.img can not be found at this

where it should say looks at /sda8 on your system.

In addition there are further sector inconsistencies on /sda5 and on /sda6 as we can see from entries like this one:

Boot sector info:  According to the info in the boot sector, sda5 starts
                   at sector 10. But according to the info from fdisk,
                   sda5 starts at sector 204799750.

Tho fix these broken sectors and likewise try to restore your Windows boot records you may want to try testdisk.


I was the same situation as you were. But I fix the problem as explain it here http://milindapro.blogspot.com/2012/01/revert-ubuntu-boot-loader-after.html.

I think you better to read my comment after the article. That will be the exact answer for your problem here.



Don't worry I have a nice solution. you will need Windows Installation Disk or Windows Repair disk.

To Create Windows 7 Repair disk , Get any PC or laptop having Windows 7. On start search menu type "CREATE System REPAIR DISK", select option comes

You will be ask for a Blank DVD, Insert Disk and Burn It, Make a .ISO file with using software named "POWER ISO" In windows 7.

With using Power ISO you will be able to Make bootable pendrive of windows 7 disk by going in TOOLS > Create Bootable USB Or PENDRIVE.

Provide it path of .iso file earlier you created. Now you will be able to run your Pendrive as a repair Disk.

To remove GRUB:

Grab a Windows recovery media or installation CD and boot from it. You should see this on a recovery media.

You should see this on an installation media. Click "Repair your computer" and you

Open the Command Prompt, then type

bootrec /fixmbr

into the Command Prompt.

Reboot your system now you will be able to load your windows 7.

  • First do this and after fix grub – Ketan Patel Aug 14 '12 at 10:30

Re install GRUB. If you have a Ubuntu Live CD and you know the partition where Ubuntu is installed this blog post will help you for sure :-)

Repair Ubuntu after installing Windows

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