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I brought a CD to upgrade my windows 7 to 8.1 pro, I use windows 7 alongside ubuntu on my PC. So if I proceed with the upgrade will the GRUB get damaged or only the windows 7 erases and 8.1 gets installed?

marked as duplicate by chaskes, bain, Eric Carvalho, Mahesh, user.dz Jul 6 '14 at 19:49

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  • You can try this question - try and have a go at Windows 8(.1) before going anywhere near installing it... – Wilf Jun 30 '14 at 12:32

To my knowledge, installing Windows 8.1 from Windows 7 will indeed overwrite your MBR, but upgrading from Windows 8 to 8.1 should not.

However if your MBR does get overwritten, it is still possible to repair it. How can I repair grub? (How to get Ubuntu back after installing Windows?)

  • 1
    @bharat Just be sure to make a backup of the data in both systems before you have a go at this. – Charles Green Jun 30 '14 at 13:21

From experience, upgrading windows should not affect Ubuntu at all. Make a backup of your files and make sure that you follow the prompts carefully coz sometimes Windows tends to see Linux files as trash and can prompt you to delete them.

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