Wubi does not check if Windows boots using UEFI

Bug #694242 reported by Franklin Tse
This bug affects 21 people
Affects Status Importance Assigned to Milestone

Bug Description

Wubi uses MBR to boot Ubuntu installed in Windows partition. When Windows boots using UEFI, the MBR does not work and thus users will not be able to boot into Ubuntu.

Wubi should either add UEFI support or warn users that UEFI is not supported before the installation.

Tags: mbr uefi wubi

Related branches

Changed in ubuntu:
status: New → Invalid
Revision history for this message
bcbc (bcbc) wrote :

Actually Wubi doesn't use the MBR to boot - it uses the windows boot manager.

Describe in more details the symptoms you are seeing. Check the Startup & Recovery settings (system properties, advance tab, click on settings under Startup & Recovery). Check the timeout is not zero, and confirm that Ubuntu is in the listed OS's.

Changed in wubi:
status: New → Incomplete
Revision history for this message
Franklin Tse (whale) wrote :

Ubuntu shows as an option on the boot menu. However, after selecting it, the following error is displayed:

File: \ubuntu\winboot\wubildr.mbr
Status: 0xc0000098
Info: The selected entry could not be loaded because the application is missing or corrupt.

I have confirmed that wubildr.mbr does exist in C:\ubuntu\winboot.

Franklin Tse (whale)
Changed in wubi:
status: Incomplete → New
Revision history for this message
Colin Watson (cjwatson) wrote :

Right now, GRUB4DOS/ntldr-img requires BIOS facilities, so even in principle it can't work on a full UEFI system (although most current UEFI systems have some degree of compatibility, but it won't stay that way forever). If the Windows UEFI boot loader is loading .efi files, though, that sounds like it has a different interface which might actually be easier to support.

I agree that we should at least warn.

Changed in wubi:
importance: Undecided → Wishlist
status: New → Triaged
Revision history for this message
bcbc (bcbc) wrote :

Any update on this bug? Here's a recent request: http://ubuntuforums.org/showthread.php?t=2070760

It seems like this will become a bigger issue soon when Windows 8 is released.

Revision history for this message
Ivan (iapazmino) wrote :


Unfortunately I'm having exactly this problem on a Dell 14z laptop which was shipped with win 8. I've downloaded and burned several boot disks and pen drives and have always come to the same end. So, from here I can confirm the issue. If I can be of any help sending information just let me know.

tags: added: mbr
Revision history for this message
loomy (loomy) wrote :

We need to start talking seriously about this folks. UEFI as implemented on common consumer motherboards is not a security conspiracy. It is just a modern BIOS replacement. And not so modern really: you've been able to buy it for years.

It works with MBR, you don't need GPT. You don't need secure boot, you don't need windows 8. You don't even need an efi partition! You just need an efi folder. This tech is wonderful because it doesn't hide stuff. The efi folder is right there to look at.

Wubi is a disk image and some boot files and settings. So, how do we update our boot files and settings to work with UEFI? We're years behind windows on this, let's catch up.

Revision history for this message
Bogdan Harjoc (harjoc-gmail) wrote :

After a couple of quick tests with bcdedit, grub4dos and grub2win, I think the problem is that the windows bootmgr refuses to load other "Real-Mode boot sectors", like wubi (grub4dos) uses.

Windows signs just the toplevel bootmanager (shim.efi, grubx64.efi, ...) which is a PE format executable. It can't sign the files containing raw bootsectors (grldr, grldr.mbr, ...). Not even if someone is willing to pay the $99.

The only option right now, as loomy posted above, is to drop a replacement .efi file for Windows' bootmgr.efi in the EFI partition, and using the UEFI API, mark that as the default bootmgr (there can't be more bootmgrs AFAICT). And ideally the bootmgr allows the option of chain-loading the windows bootmgr (otherwise we won't have full support for all the boot scenarios Windows supports).

Am I missing something ? (honest question, I hope I am)

no longer affects: ubuntu
Revision history for this message
Kingdon Barrett (kingdon) wrote :

This most certainly is still a problem, I found this issue ticket because of http://askubuntu.com/questions/225048/is-wubi-for-windows-8 and I came across the same issue today.

Same message about File: \ubuntu\winboot\wubildr.mbr

I did not see any warning about installing Ubuntu via WUBI on Windows 8 until it was too late.

It did not break my ability to load Windows 8 thankfully, but I was not able to find the solution to enable booting to Ubuntu after installing via WUBI.

Previous two posts indicate there is an easy workaround but I could not divine it. Can someone tell how to boot it?

Revision history for this message
Kingdon Barrett (kingdon) wrote :

Well I can't complain too much, 'Uninstall' did not leave the boot manager menu in an inconsistent state, so I did not need to follow cleanup steps in http://askubuntu.com/questions/239245/ubuntu-winboot-wubildr-mbr-error

Still, title of the bugreport says enough. WUBI should either warn users of potential for failure (save me a lot of download time) or provide support.

Revision history for this message
Dimitri John Ledkov (xnox) wrote :


Already has a very big banner warning about WIndows 8 and UEFI. Where else would you like a warning message?

Revision history for this message
Mateo Salta (mateo-salta) wrote :

I think one problem is that not everyone gets the WUBI installer from downloading it there.

Revision history for this message
Patrick Sweetman (sweetmanpc) wrote :

As of January 2014 there is still no Wubi-UEFI compatability. I can run Ubuntu within Win XP on my ancient laptop but not on my new 6-core desktop. This is a sad state of affairs.

Revision history for this message
Patrick Sweetman (sweetmanpc) wrote :

#10 xnox
> Where else would you like a warning message?

Wubi itself should detect fatal conditions such as dynamic drives and UEFI motherboards and warn.

Changed in wubi:
status: Triaged → Confirmed
Revision history for this message
Launchpad Janitor (janitor) wrote :

Status changed to 'Confirmed' because the bug affects multiple users.

Changed in ubuntu:
status: New → Confirmed
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