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I have Windows on one hard drive and Ubuntu on another. Last time I was in Windows and I chose to shut down the computer. It got stuck on "Exiting Windows". I could tell because it took like forever to shut down (10 minutes at least), and the circle (mouse pointer) was not spinning. So I shut it off by press and holding the power button.

Now when I power on, POST takes longer time than usual but I think it passas, or maybe it skips? Then it gets stuck after "Verifying DMI Pool Data".


The hard drive with Ubuntu has been on the decline for some time, I think it has finally failed. But the hard drive with Windows is healthy, it should be working. Why can't I boot to Windows? Is this because the bootloader is stored on the failing disk? What should I do?

Sometimes I get this:

Verifying DMI Pool Data...................
Boot from CD/DVD :

That's the normal boot, because my first boot device is the ODD. It then jumps to HDD if no CD/DVD is present.

Now it gives me this:

Verifying DMI Pool Data...................
Boot from CD/DVD :
error: no such device: a00606f0-dd69-4a57-9a06-343aab87bccb.
grub rescue>

It seems that when the failed hard drive is properly identified on startup (POST), then it boots normally. I get to the Grub boot menu and I can pick either Ubuntu or Windows. Although, sometimes it doesn't help even if the hard drive is identified. In that case, powering off and then powering on again usually solves the glitch and I am able to boot.

But when the failed hard drive is not properly identified, then it always gets stuck and the Grub rescue prompt shows up. This is also true when the failed hard drive is not present, i.e. when I disconnect it from the motherboard. The "no such device" error above refers to the missing or unidentified hard drive.

Can someone please tell me why booting Windows has to depend on a working Linux system? I primarily use Windows and it's installed on a completely different hard drive. If Windows is on HDD1, and Linux is on HDD2, and then HDD2 fails like it did here in my case, then why shouldn't I be able to boot from HDD1 with Windows? As I understand this is because Grub is installed on HDD1. So it removed the Windows bootloader? Shouldn't Grub be installed on the same hard drive as Linux, i.e. on HDD2? So that if HDD2 with Linux dies, then everything belonging to it also dies, but I can still use another hard drive with another bootloader?

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If this is a bootloader error, it's easy to fix, i mess my bootloader too many times, i became used to it! I started messing it up just to have some fun fixing it :)

Try downloading super grub 2, burn it to disk, and start the computer, if the windows still there, it should show, start windows.

Then use EasyBCD to create the bootloader.

If that didn't work then chances are it's not a bootloader error, if windows gave you some errors, then you might want to repair it.

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Can I save the Super Grub ISO to a USB stick and boot from it? – sammyg Aug 3 '13 at 18:37
@Sammy i never tried, but here's an official guide so yes you could, the guide says it's not recommended – Lynob Aug 3 '13 at 18:50
Why was Grub and Ubuntu not installed on the same hard drive? With older versions of Ubuntu (8.x) the bootloader was never installed on the same hard drive as Windows, if I chose to install Ubuntu to a separate hard drive. So back then I also had Windows on one hard drive and Linux on another. Note: Not different partitions, but different hard drives! And whenever I needed to boot into Linux I would just press F12 on POST and choose the hard drive with Linux on. That's it. But now, with latest Ubuntu it overwrites the existing Windows bootloader, even if Ubuntu is installed on another drive. – sammyg Aug 3 '13 at 20:54
@Sammy I wasn't a linux user when ubuntu 8 what around, the first linux os to install on my vps was debian lenny and ubuntu maverick, the first linux to install on my pc was linux mint 11 i believe followed by ubuntu 11.4 i think so i don't know how ubuntu used to work. But Ubuntu doesn't override the windows bootloader and thats causing a problem on my pc, i fixed my bootloader using easybcd once and then installed crunchbang, and now i have 2 bootloaders that i cant get rid of them (i had the same problem when i was using ubuntu) Maybe because i used easybcd? don't know but i have 2! – Lynob Aug 3 '13 at 21:09
I asked on this site, no one knows how to fix it, haven't gotten any replies, all i want to do is to get rid of both bootloaders, then use grubdisk to create and easybcd to create 1, anyway it's another issue, glad you fixed your issue :) – Lynob Aug 3 '13 at 21:11

Problem solved!

To remove Ubuntu and reformat the hard drive:

Skip the first two steps if you have a Ubuntu media.

  1. Download Ubuntu 12.04 or 13.04 ISO file.
  2. Burn the ISO to a CD or DVD.
  3. Boot from the Ubuntu CD or DVD.
  4. Choose "Try Ubuntu".
  5. Open a new Terminal (Ctrl+Alt+T).
  6. Type sudo add-apt-repository ppa:yannubuntu/boot-repair and press Enter.
  7. Type sudo apt-get update; sudo apt-get install -y os-uninstaller && os-uninstaller and press Enter.
  8. If OS-Uninstaller doesn't start automatically, start it manually by going to System->Administration->OS-Uninstaller menu (Gnome), or via the Dash if you use (Unity).
  9. Choose Ubuntu from the list of OS options and click OK, then Apply.
  10. Restart the computer.


To remove Grub and put Windows bootloader back in charge:

  1. Boot from the Windows DVD.
  2. Click "Repair your computer".
  3. Exit out of any dialogs till you see "System Recovery Options". Then click on "Command Prompt".
  4. Type bootrec /fixmbr and press Enter.
  5. Type bootrec /fixboot and press Enter.
  6. Close Command Prompt.
  7. Click Restart to restart the computer.


Now I can finally boot into Windows without depending on Grub or Ubuntu or a working second hard drive.

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