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On my laptop, I had Windows 7 Home Premium preinstalled. A year or so ago, I dual-booted it with Ubuntu 14.04 LTS.
I now want to upgrade Windows 7 to Windows 10 (it's free, so why not?) when it's released.
However, I'm unsure whether this will affect GRUB and stop me from accessing my Ubuntu partition. I need both operating systems and can't afford to lose either.
If this will affect GRUB, how can I restore GRUB so I can access both operating systems?
Thanks in advance.
EDIT: Just to be clear, I already have a dual-boot set up, where Ubuntu was installed alongside a pre-existing Windows installation. I now want to upgrade Windows (from 7 to 10) but am worried it will affect GRUB and my ability to boot into Ubuntu.
UPDATE: I installed Windows 10 and it ended up leaving GRUB alone. Selecting the Windows 7 option booted me into Windows 10.