In case your computers CD/DVD rom is not working when you try to install using Windows 7 DVD and it fails in middle of installation with some error.
A detailed steps to make an usb drive / pen drive as windows bootable drive. which you can use to install Windows 7 on your laptop or desktop computer.
Steps as follows :-
Open command prompt as run as administrator
C:\Windows\system32>diskpart
Microsoft DiskPart version 6.1.7601
Copyright (C) 1999-2008 Microsoft Corporation.
On computer: DURGA
DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
——– ————- ——- ——- — —
Disk 0 Online 149 GB 0 B
Disk 1 Online 7728 MB 0 B
DISKPART> select disk 1
Disk 1 is now the selected disk.
DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
——– ————- ——- ——- — —
Disk 0 Online 149 GB 0 B
* Disk 1 Online 7728 MB 0 B
DISKPART> clean
DiskPart succeeded in cleaning the disk.
DISKPART> create partition primary
DiskPart succeeded in creating the specified partition.
DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
——– ————- ——- ——- — —
Disk 0 Online 149 GB 0 B
* Disk 1 Online 7728 MB 0 B
DISKPART> select partition 1
Partition 1 is now the selected partition.
DISKPART> active
DiskPart marked the current partition as active.
DISKPART> format fs=ntfs quick
100 percent completed
DiskPart successfully formatted the volume.
DISKPART> assign
DiskPart successfully assigned the drive letter or mount point.
DISKPART> exit
Leaving DiskPart…
C:\Windows\system32>
Now copy the all the contents of the windows 7 DVD to the pen drive.
Eject the pen drive and now the pen drive is ready for boot.