In this post, I am going to emphasize on how to create a bootable USB drive with the Windows 7 installer. It's a pretty simple and straight-forward process. There are several advantages of doing this -
- Installing Windows 7 on computers without an Optical CD/DVD Drive. Many of the new laptops/desktops come without the CD/DVD drive. Using a bootable USB is very helpful here
- Installing from the USB drive is typically faster than installing from a DVD drive
- OS disc images (.iso, .nrg) need not be burned onto a CD/DVD to use them. You can make a bootable USB drive from the image and install the OS from the USB
There are two phases involved in the process - "Formatting the USB drive" and "Copying the installation files and making it bootable".
Formatting the USB drive
I am using the Diskpart command line utility in the following steps to format the USB drive. I guess even the Right-click and Format option can be used, but I haven't tried it. If you get into any trouble using the Format from the Right-click menu, put in a comment and I will look into it.
- Open the command prompt as an Administrator
- Start the DiskPart utility by typing in "diskpart". This will show a list of all the drives connected to the system. Identify the disk corresponding to the USB drive
- Select the USB drive using the "select ###" command
- Clean it using the "clean" command
- Create a primary partition on the USB using the "create partition primary" command. This is where we will be copying the installation files
- Select the partition using the "select partition 1" command
- Make it active by typing "active"
- Format the drive and create an NTFS filesystem on it using the "format fs=ntfs" command
- Assign a drive letter to the USB disk using the "assign" command
- Exit the DiskPart utility using the "exit" command
The USB is now formatted and is ready for the transfer.
Copying the installation files and making it bootable
The following steps are the crux of the process.
- Insert the Windows 7 DVD
- Navigate to the boot directory of the DVD
- There is a utility "Bootsect" which comes bundled in the Windows 7 DVD. This does the entire work for us
- Run the utility from the command line and specify the drive letter of the USB drive. bootsect.exe /NT60 X:
- The utility adds the appropriate boot-code to the USB drive
- Copy the contents of the DVD onto the USB drive
That's it, reboot the system, make sure that the USB boot is given the highest priority and the installation starts.