[Windows] Windows 8 UEFI boot broken, not fixed by boot-repair

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http://ubuntuforums.org – I installed Ubuntu in dual-boot on my Windows 8 laptop. Everything worked fine.A few days ago I updated to Windows 8.1. Ubuntu stopped booting.No problem, I ran a live USB version of Ubuntu and ran boot-repair (taking into account that I was using UEFI). Linux booted correctly, but Windows boot got weird. If I selected Windows Boot Manager at startup, the screen went black then jumped into GRUB. If I selected Windows Boot UEFI loader, I got the GRUB rescue screen.If I selected Windows UEFI bootmgfw.efi (created by boot-repair, I believe), Windows booted normally.This was annoying, so I ran boo (Hardware)