Ubuntu MATE 25.04 Installer Does Not Detect Windows in UEFI Dual Boot

Support & Help Requests
,
1

Hi, I’m trying to install Ubuntu MATE 25.04 alongside Windows on my laptop, but I’m running into some issues:

System setup:

  • Windows is installed in UEFI/GPT mode.

  • My disk has a C: partition (~200 GB) for Windows and about 281–301 GB of unallocated space for Ubuntu.

  • There’s an existing EFI partition (96 MB FAT32) and other standard Windows recovery/system partitions.

  • I created the Ubuntu USB with Rufus in UEFI mode and wrote it in DD mode to ensure UEFI compatibility.

Problems encountered:

  1. Ubuntu installer does not detect Windows:

    • The installer does not show Windows as an existing OS.

    • There’s no option to “Install alongside Windows.”

    • It suggests wiping the disk, which could risk my Windows installation.

  3. Bootloader/EFI not selectable:

    • In the installer, the “Device for bootloader installation” section does not allow selecting the EFI partition or the USB.

    • This prevents proper GRUB installation and automatic detection of Windows.

  5. Concern about EFI overwrite:

    • I’m worried that selecting the EFI partition could overwrite Windows, though I know Ubuntu usually just adds GRUB files without deleting Windows files.

  7. Known installer bug:

    • Ubuntu MATE 25.04’s installer sometimes fails to detect Windows in UEFI/GPT setups, even when the EFI partition exists.

What I’ve tried so far:

  • Created the USB in UEFI/DD mode with Rufus.

  • Checked that Fast Startup is disabled in Windows.

  • Considered using the manual partitioning (“Something else”) option with the existing EFI.

Question:

Has anyone encountered the same issue? Is there a reliable way to get Ubuntu MATE 25.04 to detect Windows automatically in UEFI mode, or is it better to use Ubuntu MATE 24.04 LTS for dual boot?

1 Like
2

I had this trouble trying to install 24.04 alongside 22.04 on a laptop to try some things not readily available on 22.04.

Consensus is the 24+ installer is crap and a total disservice to anyone looking to try Linux as an alternative to buying a new “Windows 11 ready” machine.

I briefly describe what I did,

Scrounge up a usb3 stick or spare hard drive and do a “wipe and install” of the desktop OS, being sure not to touch your existing windows disk. Verify this temporary install boots.

Get another USB3 stick and make a “Boot Repair” system and set it aside for now:

https://sourceforge.net/p/boot-repair-cd/home/Home/

Boot the installer USB stick and choose “try Ubuntu”. Open gparted from the System menu and copy the /boot/efi partition (~1.1GB fat32) and / partition from your “wipe and install” drive/USB to the unallocated space on your Windows drive.

When this completes, shutdown and remove the “wipe and install” drive, and the installer USB stick. Boot the “Boot -Repair” disk you made earlier and hopefully it automatically sets you up to dual boot windows and ubuntu by finding the existing operating systems and doing a proper multi-boot grub installation.

Far from ideal, but it bailed me out.

5 Likes
3

Hi, @il-mangia and welcome to the Ubuntu MATE Community!

1 Like
4

@il-mangia , I did the following :

  1. I did check whether Win11 encryption is disabled (Settings > Privacy & security > Device encryption)
  2. I did create an UbuntuMate 22.04 USB stick with balenaEtcher. The installer did recognize Win11 without problems. After installation + Boot
  3. Open a terminal and with sudo apt update && sudo apt upgrade install the last 22.04 updates. After all sudo do-release-upgradeto get 24.04
4 Likes
5

The installer really needs to be fixed, as this will drive away potential Linux users who are looking to try Linux as an alternative to buying a new “Windows 11 ready” machine.

Your solution is probably easier and safer than using gparted for a beginner.

2 Likes
6

All my Ubuntu USBs They were flashed with Rufus on Windows 11, which I installed on my PC. It's strange... when I had a friend try it, he found Windows all right. I don't have BitLocker or Fastboot.

7

Update: I installed Windows on the entire disk without leaving any new partitions, but nothing changes.

8

Now I’m confused, I thought you had a windows partition that you needed to keep “without risking”, but now you said you installed Windows to the entire disk and “nothing changes”.

I’d never recommend anything but a “Long Term Support” version for a dual boot setup.

Have you tried Gloster10’s solution of installing 22.04 and have it “install alongside Windows. And once complete, do the system upgrade to 24.04?

1 Like
9

SOLUTION

The new Ubuntu installer, even though the USB with the installer is a BIOS mbr, forces writing to the disk in UEFI. I had to install an old 20.04 CD and HP used that and I upgraded the version... developers fix this.

To upgrade do: sudo apt dist-upgrade

3 Likes