How to create Windows Bootable USB without any Tool

Although there are a number of software on the web that can help you create bootable windows pen drives, but doing something yourself from the scratch has  a thrill of its own.

Creating a bootable pen drive is not that hard. In fact, it is one of the most common way of creating a bootable pen drive.

Pre-requisites: Before proceeding with the steps to create a bootable windows pen drive you must have the following things - 

1. Windows Files (either from a DVD or extracted from a windows iso image file)

2. A pen drive (4GB or more)

Now make sure that you have USB plugged into your computer system and perform the following steps - 

1. Go to Start Menu, search for CMD (or command line), right click the icon and click on run as Administractor
2. After the command prompt appears, write the following commands in order
• diskpart
• list disk
• select disk <disk number>   (disk number is the number in front of the USB drive. you can recognize the USB from its size )
• clean
• create partition primary
• select partition 1 (one)
•  active
• format fs=ntfs (This command will probably take 10-15 minutes)
  
3. After the Format is complete, write the following commands in the command prompt
• Assign
4. Now you'll see that our USB drive has been assigned a letter (G or H or some other letter)
5. Type exit to exit the diskpart
6. Now we need to write the path of our executable windows file to the pendrive. For this make sure that the windows files on your system contains a boot folder with bootsect executable file.
7. Go to the folder that contains the Windows files using the cd command. For example if the windows copied files are in E:\windows 7. Then write the following commands. 
• E:  (E with a semicolon at the end)
• cd "windows 7"
  
8. cd boot
9. bootsect.exe/nt60 h:  (h is the letter assigned to the pen drive earlier. replace it with your pendrive letter)
10. exit

That's it. Now copy all your windows files to your Pendrive. Now you can boot your system from the pendrive and reinstall your operating system