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Accepted
Kelley
Asked: 2012-06-14 06:38:42 +0800 CST

A routine update wrote Grub in the MBR; how do I undo it?

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I have Ubuntu 12.04 and Windows7 installed onto a machine so that I could boot into either one. I wanted to keep using the Windows bootloader (actually EasyBCD), so I made sure that I didn't install Grub into the MBR, and all was well.

However, a week or two ago, just doing a routine update with Update Manager, it updated Grub but put it into the MBR (without telling me and without asking my permission), disabling the Windows bootloader, so now the machine boots into Grub instead. I'd like to get it back to booting into the Windows bootloader.

I've read it is easy to fix this, but I don't know how. Any help?

grub2

3 Answers

  1. Best Answer

    Go to the "BCD Deployment" menu in EasyBCD. Then click the "Write MBR" button.

    enter image description here

    Reboot, and you're all set!

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  2. To reinstall the Windows boot loader you will need to boot the windows recovery console ( possibly via the install cd ) and run the FIXMBR command.

    To make sure grub isn't (re)installed to the MBR, you need to run sudo dpkg-reconfigure grub-pc and make sure it is not configured to install to the whole drive ( /dev/sda ).

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  3. Both answers were great so I upvoted them. In the end, I found it easier than I might have imagined.

    Since I had used EasyBCD on Windows to set up the Windows boot manager, I opened it and found an option to repair the MBR. I ran it - somewhat nervously - rebooted, and it was all back to normal! Nice program!

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