I have installed Ubuntu 16.04 on a drive where I already had Win 7 installed in UEFI mode. Ubuntu installer nicely detected Windows and added it to the GRUB menu. However, when I choose the appropriate option in the menu, Windows doesn't boot showing just a black screen.
Pressing F12 I can get a so-called one-time boot menu, from which I can choose from which device a system should boot. There is a legacy section with all physical drives, and UEFI with two options: windows and Ubuntu. When I select Windows here, it starts normally. Ubuntu starts into GRUB.
How can I fix GRUB to load Windows properly?
Ubuntu was installed from USB formatted as GPT for UEFI.
sudo update-grub, and see if that fixes it. – You'reAGitForNotUsingGit Apr 04 '17 at 14:58