If you’re running on ubuntu and want to install Windows 7 without burning a disc,you can try following steps to install Windows 7 with the iso file.

Step1:Download grub4dos from:http://download.gna.org/grub4dos/grub4dos-0.4.4-2009-06-20.zip Decompress the grub.exe and put this file into root directory of Ubuntu partition (“/”).

Step2:Create a 4GB ntfs partition and paste all files from Windows7 iso into this partition.(use this GUI tool:sudo apt-get install gparted ntfsprogs.launch from system->administrator menu).
use this command to mount the Win7 iso(change “/path/to/your/iso”):

sudo mount /path/to/your/iso /mnt -o loop

then cope all files in /mnt and paste them into root directory of previous created ntfs partition.

Step3:
For Ubuntu 9.10 (use grub2):
run:

sudo gedit /etc/grub.d/40_custom

paste following into the end:

menuentry "Grub for Dos" {
insmod ntfs
set root=(hdx,y)
linux /grub.exe
}

Note:here “set root=(hdx,y)” need change,my ubuntu was installed in /dev/sda11,so it should be “set root=(hd0,11)”
then,run:

sudo update-grub

For ubuntu 9.04 and old versions(use old grub boot loader):
run:

sudo gedit /boot/grub/menu.lst

add following:

title grub4dos
root (hdx,y)
kernel /grub.exe
boot

Note:“root (hdx,y)” is different to previous one,my ubuntu partition:/dev/sda11,and here it should be “root (hd0,10)” (without quotes).

Step4:Reboot and there is a new entry in grub:”Grub for Dos”or”grub4dos”.Select it and press c to access to grub>,then:

grub>find --set-root /bootmgr
grub>chainloader /bootmgr
grub>boot

Now,we get into Win7 installation guide interface.Press Shift+F10 to cmd command line,and run following in X:/sources loation to start:

setup.exe