The system sees the USB drive as just another drive in the system. However, your system MUST be able to boot from USB devices. If you cannot boot from a USB device, then no, you cannot run Windows from a flash drive.
What you need:
– Windows 7 DVD install disc or ISO image
– USB Drive (4GB+ and as fast as you can get)
– Running Windows Operating system
– Working set of hands and eyes
– A few minutes of your life
Before going any further, make sure you have removed any important files on your drive to a safe location, or backup them in advance, you can use the free backup software (http://www.todo-backup.com/products/home/free-backup-software.htm
what we are about to do next is to erase the entire contents of the drive.
Insert your DVD of Windows 7 into the computer, but don’t start the normal install process.
Open your ‘My Computer’ and make a note of the drive numbers of both the USB drive and the DVD drive with Windows 7 files on it.
As you can see from the image above, the DVD drive is drive has letter D assigned and the USB drive is E.
Open the command prompt with admin rights. Type cmd in Start menu search box and hit Shift+Ctrl+Enter.
To keep things really easy, if you see text in upper case, it means this is what you type into the command prompt (you don’t need to type in upper case).
this loads the diskpart application we need to proceed
the image above shows our 32 GB USB drive is listed as DISK 2
so you have to type
SELECT DISK 2 (your USB Drive may have a different number, don’t follow exactly this text it depends on your usb drive)
You will get a successful response “Disk 2 is now the selected disk”
Clean Cmd USB Drive
Next we want to clean the USB drive
you will get a successful response ‘DiskPart succeeded in cleaning the disk”.
After the drive is cleaned follow the list in the image above (detailed below in list order) – you can also note the successful text responses from the OS as you enter each command.
SELECT DISK 2 (or what number your USB drive has)
CREATE PARTITION PRIMARY
SELECT PARTITION 1
Formatting can take a little time depending on the size of the drive, our 32GB unit took about 10 minutes to format - you will see a percentage readout until it is finished.
Bootable USB Final Cmd Prompt
EXIT (DISK PART will exit)
Type D: CD BOOT (substitute the “D” if necessary with the letter of your Windows 7 DVD drive)
BOOTSECT.EXE /NT60 E: (substitute the “E” if necessary with the letter of your now ready USB drive) – we are telling the system to create a boot sector file on the USB drive.
Now you can exit the command prompt and copy all the files on the Windows 7 DVD to the USB drive.
Once this step is finished you’ll be ready to boot from this drive, all you need to do is configure your motherboard bios setup to boot first from USB rather than hard drive or optical drive. If you don’t know how to do this, refer to your specific motherboard manual or search the internet.
Now, Windows 7 installation should take between 40% and 60% of the time it does from the DVD disc.