Before, my desktop pc has Windows Xp, Windows 7, and Ubuntu 11.04 ternary-boot systems installed on one hard disk. Last night I deleted whole Ubuntu partition by accident and then messed up Windows configuration files. Nothing could be more terrible! Finally, I decided to reinstall Windows7, Ubuntu 11.04 dual boot and give up XP.

I’m lazy in burning CDs/DVDs, so I used to do it using .iso image and manage to boot into live-system via current running system’s boot loader, and finally start installation while I’m in the live-system.

Now I only have a Windows 7 LiveCD and Ubuntu 11.04 iso image (stored in a ntfs partition). I installed Windows 7 into C:, and planned to install Ubuntu 11.04 using the iso without burning a disk.

Note: This is a little different to install Ubuntu without burning a disk from XP. grldr.mbr in step 3 and step 4 plays an important part!

1.) Enable Windows 7′s administrator account and login with it.

1. Launch Start menu in Windows 7, search and run lusrmgr.msc.
2. In pop-up window, double-clik User in left, then right-click on Administrator in right and launch its Properties window. Un-tick Account is disabled.
3. Right-click on Administrator again and select to change password.
4. Log out and back in with Administrator account.


1. Copy and paste ubuntu 11.04 iso image into root directory of C:.
2. Extract initrd.lz and vmlinuz from Ubuntu 11.04 iso into root directory of C:. (Default this two files will be extracted into “C:/casper”, just copy and paste them into root directory)

3.) Download grub4dos from , then:

1. Extract grldr, grldr.mbr, menu.lst, and grub.exe from grub4dos to root directory of C:. (it default creates a folder under C: and then extract files into the folder. You need copy and paste files into root directory)
2. Edit menu.lst with text edit, and add following(change iso name to yours):

title Install Ubuntu 11.04
root (hd0,0)
kernel (hd0,0)/vmlinuz boot=casper iso-scan/filename=/ubuntu-11.04-desktop-amd64.iso ro quiet splash
initrd /initrd.gz

4.) Create a boot.ini under root directory of C: and edit it with text edit. Add following:

[boot loader]
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS=”windows 7″ /noexecute=optin /fastdetect

5.) Now, reboot and you’ll see an entry “grub” in Windows 7 boot loader. Select and boot “grub” and it boots into Ubuntu 11.04 live system. Run this command in terminal and click icon on desktop to start installation.

sudo umount -l /isodevice