What causes dual boot menu / grub missing on Windows?

Common causes of dual boot menu / grub missing include: Windows Update overwrote the GRUB bootloader, UEFI boot order changed to Windows Boot Manager first, Linux EFI partition deleted or corrupted, Fast Startup in Windows preventing GRUB from loading, Secure Boot blocking GRUB, BCD (Boot Configuration Data) doesn't include Linux entry.

How do I know if I have dual boot menu / grub missing issues?

Common symptoms of dual boot menu / grub missing include: Computer boots straight into Windows — no boot menu, GRUB bootloader disappeared after Windows Update, Linux partition not accessible from Windows, Boot menu shows only Windows, not Linux, "Operating system not found" after removing a partition, UEFI boot order changed — wrong OS loads first.

Can RescuePC fix dual boot menu / grub missing automatically?

Yes, RescuePC Toolkit includes automated scripts that can diagnose and fix dual boot menu / grub missing issues with one click, without requiring technical knowledge.

Fix Dual Boot Menu / GRUB Missing on Windows

Symptoms

You might be experiencing this problem if you notice:

•Computer boots straight into Windows — no boot menu
•GRUB bootloader disappeared after Windows Update
•Linux partition not accessible from Windows
•Boot menu shows only Windows, not Linux
•"Operating system not found" after removing a partition
•UEFI boot order changed — wrong OS loads first

Common Causes

⚠Windows Update overwrote the GRUB bootloader
⚠UEFI boot order changed to Windows Boot Manager first
⚠Linux EFI partition deleted or corrupted
⚠Fast Startup in Windows preventing GRUB from loading
⚠Secure Boot blocking GRUB
⚠BCD (Boot Configuration Data) doesn't include Linux entry

Solutions

Solution 1: Fix UEFI Boot Order

1Restart and enter BIOS/UEFI (F2/Del/Esc at boot)
2Go to Boot section > Boot Priority / Boot Order
3Move "ubuntu" or your Linux bootloader above "Windows Boot Manager"
4Save and exit — GRUB should appear on next boot
5If Linux entry is missing from UEFI: the EFI bootloader needs to be reinstalled
6You'll need a Linux live USB to repair GRUB (see next solution)

Solution 2: Repair GRUB from Linux Live USB

1Boot from a Linux live USB (Ubuntu recommended)
2Open a terminal
3Identify your Linux partition: sudo fdisk -l
4Mount it: sudo mount /dev/sdXN /mnt (replace X and N with your partition)
5For UEFI: also mount EFI: sudo mount /dev/sdX1 /mnt/boot/efi
6Reinstall GRUB: sudo grub-install --root-directory=/mnt /dev/sdX
7Update GRUB: sudo chroot /mnt grub-mkconfig -o /boot/grub/grub.cfg

Solution 3: Disable Fast Startup (Prevents Boot Issues)

1Windows Fast Startup can interfere with dual boot
2In Windows: Control Panel > Power Options
3Click "Choose what the power buttons do"
4Click "Change settings that are currently unavailable"
5UNCHECK "Turn on fast startup"
6Click Save — this ensures a clean shutdown that doesn't lock partitions

FIXES THIS IN 5 MINUTES

Fix Dual Boot Menu / GRUB Missing Automatically

RescuePC Toolkit includes 109+ automated repairs that fix this problem with one click. No command line knowledge required.

Download Now - Free Trial

No credit card required • Works on Windows 10 & 11

Browse More System & Core Features Guides

🖥️Windows System & Core Features

Fix Windows System Components and Core Features — 484 guides, 3 repairs