Ubuntu – I have the iso image but wubi again downloading the whole data

You need to tell Wubi where the file is. Run wubi.exe as follows from the command line (e.g. if you placed the image in a folder called C:\UbuntuImage):

wubi.exe --dimagepath=C:\UbuntuImage\ubuntu-12.04-wubi-i386.tar.xz

Don't extract the contents before running.

PS I found it tripped over paths with spaces in them; if you find the same problem then move it to a folder as shown above.

Additional info

You can only install Ubuntu (32bit or 64bit) using the diskimage as shown above. If you want to install Kubuntu, Lubuntu, Edubuntu or Mythbuntu (or Xubuntu only on releases prior to 12.10) then you need to download the Desktop CD ISO and save it in the same folder as wubi.exe before running Wubi. Make sure that the ISO matches the release of wubi.exe and the flavour you are installing.

Note that Wubi will check the ISO MD5 sum to ensure integrity (if you run it when connected to the internet). It will still use the downloaded ISO if it's valid. However, if you disconnect from the internet it only checks the kernel and initrd md5sums so you should always check the ISO yourself.

Yes, if you have both wubi.exe and the ISO image for the same release, you can make Wubi use the ISO so it doesn't have to download the files again. This makes installation considerably faster!

1. It's advisable to check the MD5SUM on the ISO image, to make sure it's good.

2. Put the ISO image and wubi.exe in an empty folder.

   ^{Technically there could be other files in here, but it would be confusing, and once you get additional Ubuntu ISO's in there, which sometimes happens for users who are trying different versions, it would be a bad situation.}

3. Run wubi.exe to install Wubi.

That's it. With the ISO image in the same folder as wubi.exe, the Wubi installer will automatically attempt to use the ISO image (and assuming it's an ISO for the same version of Ubuntu, and the ISO is not damaged, there should be no problems).

^{Assuming everything goes well, it should be possible to install without even being connected to the Internet when wubi.exe is run. However, if possible, it's recommended to be connected to the Internet while installing Ubuntu (whether you install it inside Windows with Wubi as you plan to do, or alongside/replacing your existing Windows or other OS by by booting a CD/DVD?USB).}

Remember, the Windows installer (wubi.exe) and the ISO image should be for the same release of Ubuntu.