Requirements: USB pen drive 4GB or more
Windows vista DVD
Step 1: Download HP USB storage format tool from here and install on your computer.
Step 2: Once you finish installation, double click on HP USB storage format tool and format your pen drive in NTFS
For this, select NTFS from File system option and Check quick format option and click on start.

While doing the format the data stored on your Pendrive will be lost. You keep a back if needed. Press YES on the warning message

Once the format finished you will get a message with the details and Click on OK

Now insert Windows vista DVD in to DVD Drive and go to command prompt.
For that go to start -> RUN and type CMD and press enter or OK

You will see the command prompt with black back ground
Now you need to change the directory to your DVD drive where you put the windows vista DVD.
For that type G: and press enter (here I am using G because in my system DVD drive letter is G. So you need to check your DVD drive letter and type accordingly)
So the directory will change to G:>
Now type cd boot and press enter
Now the interface will be like G:boot>
Then type bootsect.exe /nt60 h: (where h is the drive letter of your pen drive)
Now you will get a successful message like below

Now you can close the command prompt and copy all the contents from the windows vista DVD to the pen drive

It will start copying now

Once it’s finished, you need to restart your pc and access the bios of your system and make first boot device as USB pen drive.
That’s it, now you can see installation starts from the USB pen drive.
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