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I have a notebook (HP) with Windows 10 and I installed Ubuntu 18.04 to drive partition. I tried setup dual boot but it is not working properly. GRUB displays only Ubuntu and FreeDOS (Located /dev/sda1, but Windows location is /dev/sda2. When I select FreeDOS, it loads Windows 10, but there is drive check on each startup and loading the system is quite slow). I tried boot-repair in Ubuntu (that do nothing) and EasyBCD in Windows, but after reboot, I got the message "No bootable device -- insert boot disk and press any key". Also sudo os-prober or sudo update-grub did not help. I tried manually adding Windows to grub by pasting

menuentry 'Windows 10' {
    search --fs-uuid --no-floppy --set=root 01D4B40926AFD570
    chainloader (${root})/EFI/Microsoft/Boot/bootmgfw.efi

into /etc/grub.d/40_custom (01D4B40926AFD570 is correct UUID), but after selecting Windows 10 in grub menu, I got message "error: file /EFI/Microsoft/Boot/bootmgfw.efi not found.". Does anybody knows solution for this?

marked as duplicate by karel, Kulfy, waltinator, Eric Carvalho, Thomas Jun 1 at 12:22

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  • 2
    You must be careful not ot mix UEFI installs with BIOS installs on newer UEFI hardware systems. May be best to see details, use ppa version with your live installer or any working install, not older Boot-Repair ISO: Please copy & paste link to the Boto-info summary report ( do not post report), the auto fix sometimes can create more issues. help.ubuntu.com/community/Boot-Repair sourceforge.net/p/boot-repair/home/Home – oldfred Jan 25 at 22:58
  • The summary is there – Alex Jan 25 at 23:33
  • I forgot mention that the Windows 10 was upgraded from Windows 7, maybe that can be the problem, but I don't understand why is Windows 8 in summary when I never use Win8. – Alex Jan 25 at 23:38
  • 1
    Most Windows 7 installs were BIOS on MBR partitioned drives. Only a few have been UEFI, but users can install in UEFI boot mode ,if newer hardware. How you boot install media, UEFI or BIOS is then how it installs. And Windows only installs in UEFI boot mode to gpt partitioned drives and only in BIOS boot mode to MBR partitioned drives. – oldfred Jan 26 at 4:23
  • I add following code and it works, there is no chkdsk on startup, but still seem a quite slowly menuentry "Windows 10 (loader) (on /dev/sda2)" { insmod part_msdos insmod ntfs set root='(hd0,msdos1)' chainloader +2 } – Alex Jan 27 at 10:02