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I'm new to Ubuntu... I went to the downloads page and downloaded the Windows Installer as I am hoping initially to have a dual boot on my currently Win 7 PC (I would consider preserving my Win7 install as a VM under Ubuntu instead - advice?)

It's asking me to choose an "Installation size" but there's no explanation as to what the significance of this is. Is this a disc partition? Can I increase it easily later if it's too small?

I came here to ask these questions and now I see a bunch of threads about 'WUBI' and possible downsides of installing Ubuntu this way. Is the Windows Installer I just downloaded going to give me WUBI?

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Post a screen-shot of that. It will help others to provide the correct answer you seek. – Curious Apprentice May 12 '12 at 18:54
it's the same installer screen shown in step 3 of the help page: ...but the help page doesn't actually give any help about what the options on the screen mean. – Anentropic May 14 '12 at 10:02
up vote 7 down vote accepted

As you have established, you have downloaded WUBI.

The "Installation size" options lets you decide the amount of space you want to "give up" for WUBI. That is the space wubi's Ubuntu install is able to use. Wubi creates a disk image (loopmounted device) on your host system in/on which Ubuntu is installed. This can be compared to a kind of "safe partition" on your system.

This means the space you reserve for Wubi is not usable for your host system any more (in fact it is not even accessible from within the host system without external programmes. Ubuntuforums: Accessing Wubi Disks from Windows , AskUbuntu: How to open wubi's .disk files under windows?). Windows 7 (any Windows for that matter) will count the space you reserve for your Wubi install as occupied since Wubi just creates a file of exactly the amount of space you specified (let's say 20 GB) on your host system's harddisk, regardless of the space actually occupied in your Ubuntu Wubi system.

Apparently, there are ways to resize the wubi virtual disk (Help.Ubuntu: ResizeWubiDisk, Ubuntuforums: HOWTO: Resize the WUBI virtual disk).

You need to reserve enough space for Wubi to install Ubuntu and - if you want to use it properly - to install programmes. Additionally, you will want to have some space for documents etc.

So I'd recommend no less then 8GB of space, maybe even as much as 20GB if you can spare that much.

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Here's the Ubuntu (32 Bit Desktop) ISO download link:

Here's the Wubi download link:

share|improve this answer - Read this to learn how to use Wubi to Install Ubuntu 12.04. – Curious Apprentice May 12 '12 at 18:52
None of this answers my questions above – Anentropic May 12 '12 at 19:03
well, actually the comment answers partly thanks, it appears I've got WUBI then – Anentropic May 12 '12 at 19:09

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