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Windows 8.1 came pre-installed in my laptop, I installed Debian 8 on dualboot, the day before yesterday I had to reset BIOS settings, after resetting BIOS is also reseted MBR for windows only, system kept booting windows. I tried several fixes but didn't work. I re-installed Debian 8 and installed a few updates and did sudo reboot. Now again it boots directly into Windows instead of showing grub2 menu for dualboot. Most of the time I like to use debian for it's speed performance and other awesome stuff but I sometimes also need windows for a few tasks. Any solution? >.> It's driving me crazy...

marked as duplicate by terdon Jun 7 '15 at 10:32

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  1. Take a copy of any live Linux distro you like (I usually use my old Ubuntu CD)
  2. Boot live session
  3. Install boot repair (On Ubuntu - sudo add-apt-repository ppa:yannubuntu/boot-repair sudo apt-get update sudo apt-get install -y boot-repair boot-repair )
  4. Let it scan everything
  5. Click on recommended repair
  6. Reboot your system

This works for me almost every time.

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