Ubuntu 11.04 is no longer supported, ever since April 28, 2011. See this page for details. When a release is not supported anymore we call it EoL (end-of-life).
At least currently, Wubi cannot automatically download the files needed to install an EoL release. You must provide all the necessary files. (A 404, or File Not Found, error will occur otherwise.)
To do this:
If you have just
Wubi.exe, saved to your hard drive:
Download the ISO image for the release. Make sure to get the one for the right architecture. If you have a 64-bit machine you can use the
amd64 (64-bit) or
i386 (32-bit) version. If you have a 32-bit machine you can only use the
ISO images for old releases can be downloaded at
Save the ISO image to your hard disk. Then there are three ways you can proceed:
Make sure the downloaded ISO image it's in the same folder that contains
Wubi.exe. Then run
Alternatively, if you have an archive manager for Windows like 7-zip that is capable of extracting ISO images as though they are compressed archives (even though they really aren't), you can use that to extract the ISO image into its own folder with nothing else in it. Then find
Wubi.exe in that folder (it's one of the files that was extracted) and run that.
If you want, you also have the option of burning the ISO to a CD/DVD or writing it to a USB flash drive. That will work, and on rare occasion might make sense if you're having a lot of trouble getting Wubi to find your downloaded ISO. But generally this way is harder and takes longer.
If you're running
Wubi.exe from an Ubuntu CD/DVD or USB flash drive that you've burned or written from an Ubuntu ISO:
Wubi only gets to the point where the error occurs after checking to make sure the necessary files for installation aren't already present and usable. So they are either not present, or one or more of them is corrupted.
Either way, there's two causes: either the ISO is corrupted, or the burn/write was bad (or modified afterwards). You can find out which by MD5 testing the ISO. Then rewrite it to the USB drive, burn it to a new disc, or (if the ISO is what's bad) download the ISO again.
(And then you can use one of the techniques described above, which are faster than having to make a disc or write to a USB drive.)
If you're running
Wubi.exe from a virtual drive mounted from an Ubuntu ISO:
Some programs exist to mount ISO images in Windows as virtual drives. This is a somewhat popular way to install Wubi. If you're doing this and getting the error, then the same problem is happening as above. Since there's no actual physical Ubuntu disk, that means the ISO is bad. (Or that there's some problem with your drive virtualization software.)
The Caveat (and better solution, really)
When Ubuntu releases are EoL, you really shouldn't use them. You can't get as good support, the software on them is old, and most importantly, newly discovered bugs are not fixed. That means that there are lots of security bugs that are discovered and fixed only in supported releases. Users of EoL releases remain vulnerable. So it is actually dangerous to continue using an EoL release.
If you choose to continue using an EoL release of Ubuntu, we will respect that, but we may not be able to help you with problems (as most of us have moved on), and it's important you understand the disadvantages and risks.
Currently supported Ubuntu releases are 10.04.4 LTS, 11.10, 12.04.1 LTS, and 12.10. You can get them all here. Both ISO images and Wubi.exe installers are available for each supported release. This is highly recommended!
Technically, 8.04.4 LTS is also supported, but only for limited server use, which doesn't include GUI, community-community packages, or Wubi.
If you can't decide which version to use, it's usually best to go for the latest release (as most people do) or the latest LTS release.
Traceback (most recent call last) line means this is a crash, which is a type of bug. Therefore, as Jorge Castro says, you should report this as a bug (against the Wubi project on Launchpad).
However, the fundamental problem here would probably not be considered a bug, and you can solve it pretty easily. See above for solutions, or below for an explanation.
They key to understanding what's going on lies in the output just before the crash:
12-27 15:15 DEBUG CommonBackend: Searching for local ISO
12-27 15:15 DEBUG CommonBackend: Could not find any ISO or CD, downloading one now
12-27 15:15 DEBUG TaskList: New task get_metalink
12-27 15:15 DEBUG TaskList: ### Running get_metalink...
12-27 15:15 DEBUG downloader: downloading http://releases.ubuntu.com/11.04/ubuntu-11.04-desktop-amd64.metalink > G:\ubuntu\install
12-27 15:15 DEBUG downloader: Download start filename=G:\ubuntu\install\ubuntu-11.04-desktop-amd64.metalink, url=http://releases.ubuntu.com/11.04/ubuntu-11.04-desktop-amd64.metalink, basename=ubuntu-11.04-desktop-amd64.metalink, length=28363, text=None
12-27 15:15 DEBUG downloader: download finished (read 28363 bytes)
12-27 15:15 DEBUG downloader: downloading http://releases.ubuntu.com/11.04/MD5SUMS-metalink > G:\ubuntu\install
12-27 15:15 ERROR TaskList: [Errno 14] HTTP Error 404: Not Found
First, Wubi tries to find an Ubuntu ISO image on your computer. You don't have one--you probably just downloaded
Wubi.exe (which is ordinarily a perfectly good thing to do). Then Wubi tries to download the ISO.
It connects to the
http://releases.ubuntu.com server. But Ubuntu 11.04 is no longer supported--it is an end-of-life release. EoL releases are stored on a different server, accessible at
http://old-releases.ubuntu.com. Some data on the
releases server will redirect to the
old-releases server automatically, but most will not; in particular, trying to download files that are actually part of an old distribution will fail. So Wubi downloads the initial
.metalink file successfully but fails to download the first file that's part of Ubuntu 11.04 (which happens to be
This also explains why you can solve this by providing the ISO image yourself.