Missing Windows from Grub After Dual Boot? Here’s What You Can Do

So, you’ve just installed Linux alongside Windows, expecting a sleek GRUB menu letting you choose your OS at startup—but Windows is nowhere to be found. Don’t panic. This is a common dual boot hiccup, and it’s usually easy to fix.

Here’s what’s going on and how to get Windows back on your boot menu.

Why Windows Disappears from GRUB

During a Linux install, especially with distros like Ubuntu, the GRUB bootloader takes over. It should automatically detect other operating systems (like Windows) and add them to the boot menu. But sometimes it doesn’t—either because:

• Windows was installed in UEFI mode and Linux in Legacy (or vice versa).
• The Linux installer didn’t detect Windows.
• The GRUB config wasn’t updated after installation.

Step-by-Step Fix

✅ Step 1: Boot into Linux

Start your system. If GRUB loads but doesn’t show Windows, boot into Linux.

🔧 Step 2: Update GRUB

Open a terminal and run:

sudo update-grub

This forces GRUB to rescan all disks for OS installations. If it finds Windows, you’ll see something like:

Found Windows Boot Manager on /dev/sda1

Then reboot. Windows should now appear in the GRUB menu.

🔍 Step 3: Check EFI Partitions (If That Didn’t Work)

If you’re using UEFI, your system might have multiple EFI partitions, or GRUB might not be looking in the right one. Check with:

sudo os-prober

If it detects Windows, try running sudo update-grub again.

Still no luck? You might need to reinstall GRUB properly:

sudo grub-install
sudo update-grub

Make sure you’re installing GRUB to the right disk (usually /dev/sda, not a partition like /dev/sda1).

Bonus: Use Boot Repair (For Ubuntu-Based Distros)

If all else fails, try Boot Repair—a GUI tool that can fix boot issues automatically.

Install it with:

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt update
sudo apt install -y boot-repair

Then launch it and follow the recommended repair steps.

Last Resort: Check BIOS/UEFI Boot Order

Sometimes the system boots straight into Windows, skipping GRUB. In that case:

• Enter your BIOS/UEFI settings (usually by pressing F2, DEL, or ESC at startup).
• Make sure the Linux bootloader (like “ubuntu”) is set as the first boot option.

Final Thoughts

Missing Windows from GRUB after dual booting is annoying but fixable. Most of the time, a simple update-grub does the trick. If not, tools like os-prober or Boot Repair can help you out.

Remember: always back up important data before messing with bootloaders.

Got stuck or have a weird setup? Drop a comment below—I’ll try to help.