Make a pen drive bootable

For me a bootable USB pen drive has many advantages over other boot drives such as speed, a pen drive is much faster to boot than CD/DVD.  Is easier to modify the files on the drive and much more.  There are many ways to create a bootable usb pen drive,  I will list all the methods i know of here.  First of all make sure you backup any data that might be on your usb pen drive. 
Method 1 – Create a Bootable USB Pen Drive using HP Drive Boot Utility 
  Insert your usb pen drive in to your computer and format it with fat32 file system.
 Download the required files from google.
Once downloaded extract the files in to a new folder on your computer.

 Open up the folder and double click on the file HPUSBFW.exe.  Under the drive select the drive letter of your usb pen drive, then under file system select fat32. Tick “Quick Format”  Tick the box “Create a DOS startup disk”  press … and browse to the folder you just extracted to on your computer, Select the folder “BOOT_DISK_FILES”   Click OK > Start > YES 
Make sure the USB drive is still plugged in to your computer and reboot your machine, your machine will now boot to the  usb pen drive and will display you with a ms-dos window. 
Method 2 – Create a Bootable USB Pen Drive using Bart’s mkbt Kit 
  This method requires that your system has a floppy drive, if you don’t have a floppy drive move on to the next method.  Download the required files from herePut a bootable floppy disk in to your floppy drive.  Extract the files you downloaded to a folder on your computer.  Now open the command prompt by clicking start > run > type in cmd and press enter, in the black window type in   cd %LOCATION_OF_FILES%      replace %LOCATION_OF_FILES% with the location of the folder you just extracted.  For Example    cd C:\Temp    Then type     mkbt -c a: bootsect.bin 
  The boot sector will be extracted from the floppy drive and copied to the folder that you extracted the mkbt kit to.   Now format your USB pen drive with either fat or fat16 file system.  Go back to the command prompt and type in    mkbt -x bootsect.bin Z:     replace Z: with the drive of your USB pen drive.  Now leave the USB Pen Drive in the computer and reboot the computer,  The computer will now reboot to your pen drive. 
Method 3 – Create a Bootable USB Pen Drive using UNetbootin 
  Download an MS-DOS ISO from Here, Download UNetbootin from UNetbootin – ISO to Bootable USB Drive extract both files and double click on unetbootin-windows-494.exe.    Select the Diskimage radio button, make sure ISO is listed and then browse to and select the .ISO file you just downloaded.  Next to Type: Make sure USB Drive is selected and the drive of your USB drive is selected.  Now click on ok.  You now have a bootable USB Pen Drive. 
Method 4 – Create a Bootable USB Pen Drive using Windows 98 
If you are still using windows 98 there is a very easy way to make a bootable USB Pen Drive.  Click on start > Run > type in cmd and hit enter, then type in   SYS E:    or   FORMAT E /U /S    replace E with the drive letter of your USB Pen Drive 
Method 5  – Create a Bootable USB Pen Drive using UNetbootin 
  Download the freedos ISO from Here, Download UNetbootin from UNetbootin – ISO to Bootable USB Drive extract both files and double click on unetbootin-windows-494.exe.    Select the Diskimage radio button, make sure ISO is listed and then browse to and select the .ISO file you just downloaded.  Next to Type: Make sure USB Drive is selected and the drive of your USB drive is selected.  Now click on ok.  You now have a bootable USB Pen Drive. 
Method 6 – Create a Bootable USB Pen Drive using WinToflash 

Download WinToFlash from here  extract the file and double click on the extracted file and follow the prompts. 
Method 7 – Create a Bootable USB Pen Drive using Kevins Blog Method
This method is from Kevins Blog 
1. Insert your USB (4GB+ preferable) stick to the system and backup all the data from the USB as we are going to format the USB to make it as bootable. 
2. Open elevated Command Prompt. To do this, type in CMD in Start menu search field and hit Ctrl + Shift + Enter. Alternatively, navigate to Start > All programs >Accessories > right click on Command Prompt and select run as administrator. 
3. When the Command Prompt opens, enter the following command: 
DISKPART and hit enter. 
LIST DISK and hit enter. 
Once you enter the LIST DISK command, it will show the disk number of your USB drive. In the below image my USB drive disk no is Disk 1. 
4. In this step you need to enter all the below commands one by one and hit enter. As these commands are self explanatory, you can easily guess what these commands do. 
SELECT DISK 1 (Replace DISK 1 with your disk number) 
CLEAN 
CREATE PARTITION PRIMARY 
SELECT PARTITION 1 
ACTIVE 
FORMAT FS=NTFS 
(Format process may take few seconds) 
ASSIGN 
EXIT 
Don’t close the command prompt as we need to execute one more command at the next step. 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 “D” as my optical (DVD) drive letter and “G” as my USB drive letter. 
6. Go back to command prompt and execute the following commands: 
6.1. Change directory to the DVD’s boot directory where bootsect lives: 
d: 
cd d:\boot
6.2. Use bootsect to set the USB as a bootable NTFS drive prepared for a Vista/7 image. I’m assuming that your USB flash drive has been labeled disk G:\ by the computer: 
bootsect /nt60 g: 
(Where “G” is your USB drive letter) 
7. Copy Windows DVD contents to USB. 
You are done with your bootable USB. You can now use this bootable USB as bootable DVD on any computer that comes with USB boot feature (most of the current motherboards support this feature). 
Note that this bootable USB guide will not work if you are trying to make a bootable USB on XP computer. 
Method  8 – Easily Create a Bootable USB Pen Drive in Windows 9X 
  If you are using Windows 9X (Windows 95, ME or 98) There is an easy way to create a bootable usb pen drive.  Click on start > run and then type in the black window   sys e: at a c:\   replace e: with the drive of your usb pen drive.  
  Or, from Windows, goto Start | Settings | Control Panel | Add Remove Programs | Startup Disk | Create Disk. You may be asked to insert your Win9X CD.  Now leave the usb pen drive in your computer and reboot your system. 
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