Why won't Grub boot Windows 10?

Question

linux

There is a computer with Windows 10 and UEFI, later installed Linux Mint. But when starting via Grub, Windows 10 starts automatic repair. By F12 (disk selection) UEFI Ubuntu and UEFI Windows appear. Individually they load fine. In which direction to dig? Grub-update Windows sees, adds.

Answer 1

Is GRUB EFI installed? It won't work without it.