When I installed Backtrack 5 R3, I chose to dual boot, it completely erased my BIOS and installed GNU Grub as the first thing that shows up when I boot up.

The "Press escape for startup options" output still shows, but if I press escape, it says "BIOS is missing or corrupted". I would like to boot the Windows installer from my USB stick (testing out Windows 10), remove GNU GRUB, and flash back my BIOS while still being able to dual boot Backtrack 5 R3.

  • I think it's very unlikely that there's anything wrong with your BIOS. However, installing Grub certainly replaced your disk's old MBR and Windows gets confused by non-Windows MBRs. Unless you made a backup of the MBR the easiest way to get things back into a state that Windows can cope with is to run the Windows Fixmbr utility. – PM 2Ring Oct 25 '14 at 13:58
  • Ok well how am I supposed to get into the recovery console then? I can't boot to anything other than the installed windows 7 or backtrack from Grub. – Spencer123 Oct 25 '14 at 22:34
  • If you don't have any Windows install or recovery disks, you can download an .iso for a recovery disk from Microsoft. See this answer – PM 2Ring Oct 26 '14 at 4:01

I found the answer over on SuperUser.

At the Grub menu press "C" to get to the Grub command line. Typing ls at the command prompt will list the devices grub has found.

grub> ls

Of course it may be difficult to determine which drive is the USB stick you want to boot. You can ls within the devices to try to figure that out.

grub> ls (hd0,1)/

Once you find the proper device, set it to root.

grub> set root=(hd0,1)

Or the older syntax:

grub> root=(hd0,1)

After setting root, enter these commands do boot using the bootloader on the device:

grub> chainloader +1
grub> boot

This should work with any bootable disk.


Ok I finally figured it out. My BIOS actually was corrupted so I replaced the BIOS chip, booted to recovery console from recovery disk, and then fixed my MBR. I can finally boot into something other than Windows and Backtrack!

Not sure how to get into Backtrack now, since it just boots straight into Windows, but that's not important.

Thank you PM 2Ring for your help!

  • Your motherboard manufacturer might have had a tool to flash the BIOS from Win7 instead of replacing the chip. Your fixed MBR probably overwrote Grub. Grub can probably be restored to boot into your Backtrack install using tools available after booting just about any Linux installer or "Live" disk. – robartsd Jul 30 at 15:40

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.