hi all it is very simple to do that..
First download this file.
install it.
Make an ISO file of window 7 DVD.
And make sure u have a pen drive of minimum 4GB.
after that run the Windows7-USB-DVD-tool, which you have downloaded and installed, from your desktop icon and follow the steps.
it will take some time.
after completing this. make USB 1st priority for booting in BIOS then restart
it will work enjoy....
