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I had dual boot windows 8 and ubuntu precise pangolin 12.04. I upgraded to windows 8.1. It broke grub. So I used a live usb to run ubuntu and ran boot repair. However, it tells me I have to download the 64 bit CD iso. I did that. But what do I do with it now?


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up vote 2 down vote accepted
  • After downloading 64 bit boot-repair disk iso file,you have to burn it into cd or make a bootable Boot repair USB through unetbootin.

  • Then boot from the boot-repair live disk.Because you installed Ubuntu in UEFI mode, you have to give the partition where EFI files are located by clicking advanced option in boot-repair(not recommended repair).

  • Then run it.After the successfull completion of boot-repair, shutdown your pc and remove the boot-repair live disk.

  • Now change the boot order in bios to set HDD as the first option.Save the changes and exit out of the bios.

  • Grub will appears on startup with all the OS's entries.

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Hi Avinash - thanks for that. One problem is I don't have a cd drive. So I'm trying to do it via USB. I've followed the instructions on the boot repair web page - I've booted via the USB with the 64bit iso on it, live run ubuntu, installed boot repair via the terminal - I just cut and paste the commands on the webpage: sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update Then: sudo apt-get install -y boot-repair && (boot-repair &) Then I run boot repair, recommended repair, but I keep getting the same error - 64bit iso required. What am I doing wrong? Thanks! – Darren Feb 25 '14 at 8:46
is that the error message appears after clicking on recommended repair or at the end? – Avinash Raj Feb 25 '14 at 8:56
It shows a progress bar (scanning systems, OS prober) and then shows an error "EFI detected - Please check the options". I click OK. It gives me the option to run recommended repair. I start this - it shows "applying changes". Then it shows "EFI detected. Please use Boot-Repair-Disk-64bit ( which contains an EFI-compatible version of this software." And finally "Operation aborted" – Darren Feb 25 '14 at 11:22
Then download 64 bit boot-repair.iso file.Make it bootable and then boot from it.Because you installed Ubuntu in UEFI mode, you have the give the partition where EFI files are located by clicking advanced option in boot-repair(not recommended repair) – Avinash Raj Feb 25 '14 at 11:28
Okay - it worked! It was the EFI part I missed. Thanks Avinash, you've been fantastic! – Darren Feb 28 '14 at 13:05

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