How to make bootable USB using Cammand Prompt ?

It is very useful for netbook users or a PC or Laptop having no CD-ROM or damaged. Using bootable USB OS installation process may be very slow but it will be helpful some critical situation.

To create a bootable Operating System on USB first You need following requirements :

Windows 7 OS
USB Flash Drive (4GB or More)
Windows 7 Installation CD

Steps:-
1. Insert your USB Flash Drive to the system and backup all the data from the USB because we are going to format the USB to make it as bootable.

2. Open Command Prompt (To open Command Prompt in Windows 7 do this, Search CMD in Startmenu or Start > All programs >Accessories > right click on Command Prompt and select run as administrator OR Press Windows Key +R and type " CMD " in Run.

3. When the Command Prompt opens, enter the following command:

"DISKPART" and Press enter.

"LIST DISK " and Press enter.

Now, it will show the disk number of your USB drive. For example, In the below image my USB drive disk no is Disk 1.

4. In this step type all the below commands one by one and Press enter.

SELECT DISK 1 (Replace DISK 1 with your USB disk number)

CLEAN

CREATE PARTITION PRIMARY

SELECT PARTITION 1

ACTIVE

FORMAT FS=NTFS

(Format process may take few seconds)

ASSIGN

EXIT

Don't close Command Prompt .just minimize it.

5. Insert your Windows DVD in the optical drive and note down the drive letter of the optical drive and USB media. Here I use “G” as my optical (DVD) drive letter and “K” as my USB drive letter.

6. Go back to command prompt and execute the following commands:

Enter into G drive. To do this just type G: and press Enter

G:CD BOOT and hit enter. Where “D” is your DVD drive letter.

CD BOOT and hit enter to see the below message.

BOOTSECT.EXE/NT60 K:

(Where “K” is your USB Flash drive letter)

7. Copy Windows DVD contents to USB.

you can use XCOPY command

In command Prompt enter to CD-ROM (Just Type G: and press Enter)

Then Type

XCOPY *.* K: (K is my USB Flash driver Letter)

You are done.Your bootable USB readt now. You can use this bootable USB as bootable DVD on any computer that support USB boot feature (most of the current motherboards support this feature).