How to Install Windows 7 Via a USB Drive

This was driving me crazy.

I searched high and low and it took me far longer than it should have, but I finally figured out how to install Win7 from a USB drive WITHOUT having to create an ISO or do anything too crazy. The hardest thing that I had to do was alter my BIOS settings to make the USB drive the primary boot device. So, what follows is the steps I took to make the bootable USB drive that would install Win7 on my HTPC. First some warnings; Make sure you back up all your important files and programs before you begin otherwise all of your data will be lost. Also, make a list of your most important programs so you can re-install them after Windows 7 finishes installing. Things like; web browser of choice, antivirus, media player, etc.

Things you will need:

• USB thumb drive at least 4GB in size
• Access to your BIOS (usually by pressing a key like the delete key or F1 as soon as the computer begins to boot up)
• A copy of Windows 7 with a valid product activation key
• A WORKING computer running Windows
• About 1 hour of time

Now, on to the instructions.

Step #1 – Thumb Drive
Plug in your USB thumb drive and make sure it’s empty. If it has files on it they will be destroyed in the next step, so either copy them to a safe place or delete them now.

Step #2 – Command Prompt Window
You need to open a command prompt window with Administrator rights. Don’t worry, I’ll walk you through this Geeky stuff. It’s actually very simple, so don’t get scared. If you’re using Windows Vista or Windows 7 to create this USB Boot Drive, then all you need to do is go to the Start Orb and type “cmd” in the search box (without the quotation marks). When you see cmd.exe in the results RIGHT CLICK on it and choose “Run as Administrator”. A warning will popup, just click “YES” and a black window with white text will show up. That is the command prompt and you should see a blinking underscore on the screen right after some text. If you’re using Windows XP then you need to go to All Programs | Accessories | Command Prompt.

Step #3 – Find USB Thumb Drive Letter
In order to do the next step, which is formatting the USB thumb drive and making it a bootable device, you need to know what drive NUMBER the USB thumb drive has been assigned. This is different than the drive letter you might see in Windows. At the command prompt type DISKPART and then press ENTER.
Now, you should see the blinking underscore next to the word “DISKPART”.
Next, type LIST DISK and press ENTER.
You will see a list of all the disks in your system beginning with your primary hard disk. Find your USB drive in the list (it’s probably the one with a size of 4GBs or whatever size your thumb drive is) and note what drive number it is. For the rest of this excercise I’m going to assume the USB disk number is DISK 2, but you should substitute your disk number for mine in the next step.

Step #4 – The Commands
You need to type in the next few commands, one at a time, and press ENTER after each command. When you get to the format step, be aware that it might take a while to finish, so have something handy to keep yourself occupied until it’s done.

• SELECT DISK 2
• CLEAN
• CREATE PARTITION PRIMARY
• SELECT PARTITION 1
• ACTIVE
• FORMAT FS=NTFS (this will take a while)
• ASSIGN
• EXIT

Leave the command prompt window open, you will need it again soon.

Step #5 – Drive Letters
Now you need to insert the Windows 7 DVD into your DVD drive. When you do this, hold down the “SHIFT” key on your keyboard. This should halt the autoplay feature and let you continue without having to exit the auto-installation routine. Once the DVD is spinning nicely open up “My Computer” and note the drive letters for both the DVD drive with the Windows 7 DVD in it and the USB thumb drive. For the next steps I’m going to assume that the DVD drive is drive letter “E” and the USB thumb drive is drive letter “G”, but don’t forget to substitute your drive letters for the next steps.

Step #6 – BOOTMGR
Now you need to make the USB thumb drive bootable. We do this by going back to our command prompt window and entering the following commands.

• E: CD BOOT and press ENTER. Substitute “E” for your DVD drive letter.
• CD BOOT and press ENTER. This is NOT a repeat of the previous step.
• BOOTSECT.EXE /NT60 G: and press ENTER. Substitute “G” for your USB thumb drive letter.

Once that is done you can close the command prompt window, we’re all done with it. Now you have a USB thumb drive that is bootable and we’re almost done with all the Geeky stuff.

Step #7 – Copy Windows 7 to USB Thumb Drive
Open Windows Explorer, navigate to the Windows 7 DVD and copy all the contents of the DVD to your USB thumb drive just like you would for any other files you needed to copy.

Step #8 – Change BIOS Boot Sequence
This is the hardest part, because this part is where you need to do a bit of work on your own. What you need to do is change the boot sequence of your computer so it will boot from the USB thumb drive you just created INSTEAD of from your hard drive or CD/DVD drive. You do this by pressing a certain key (usually the DEL key, the ESC key or F1 before Windows loads while the system is starting up) and that will bring you to a very ugly screen that can only be navigated by the keyboard (no mouse). Once there, find the boot menu and change the sequence. If you can’t figure this out on your own, then please find a resident Geeky friend who can help you, because each motherboard has a different BIOS so I can’t really give you specific instructions for this step.

Once Windows 7 has installed it will need to restart the computer to finish the installation. During this restart, remove the USB thumb drive and get back to the BIOS and reset the boot sequence so the computer boots from the hard drive first and CD/DVD drive second and NOT the USB thumb drive (remove the USB thumb drive option completely). Once you have the boot sequence back to “normal” save and exit the BIOS and Windows 7 should finish installing without a problem.