Posey's Tips & Tricks
Making a USB Flash Drive Bootable (Perfect for Running Windows 8)
Brien walks you through the process of creating and running Windows 8 from a bootable USB flash drive.
Last month I discussed in one of my blog posts about putting Windows 8 onto a tablet by booting the tablet from a USB flash drive and then installing the new operating system. A few days after I submitted that particular blog post it occurred to me that there is quite a bit of confusing and sometimes contradictory information on the Internet regarding making a bootable USB flash drive. That being the case, I wanted to share with you the technique that I used.
Before you can make a USB flash drive bootable, you will need a computer that is running a Windows operating system and you will need a copy of the Windows installation media. When I set up the flash drive for installing Windows 8 onto a tablet, I used a computer that was running Windows 7 and I used a Windows 8 DVD. However, there are lots of different uses for bootable flash drives besides just installing Windows 8 onto a tablet, so you will be happy to know that a Windows 8 DVD isn’t a requirement. In fact, this procedure works just as well with a Windows 7 or a Windows Server 2008 DVD.
With that said, you can get started by plugging your USB flash drive into a computer that is already running Windows. After doing so, open an elevated Command Prompt (by using the Run As Administrator option) and then enter these commands:
The List Disk command shows every disk in the system. Each disk has been assigned a number. In my case the number corresponding to the USB flash drive was 1, so I will use that in my examples. If your computer assigns a different number to your USB flash drive then you should use that number instead.
With that said, enter these commands:
Select Disk 1
Create Partition Primary
Select Partition 1 (the 1 in this command refers to the partition number, not the disk number so you should always use 1)
When you enter the Assign command, Windows will assign a drive letter to your USB flash drive. Be sure to pay attention to the drive letter because you will need it in a moment. On my system Windows assigned drive H: to the USB flash drive, so that is what I will be using in my examples.
Now go ahead and insert your Windows installation DVD. On my system the letter of my DVD drive is E: so I will be using that, but you should use the drive letter that is assigned to your DVD drive. With that said, enter these commands:
Bootsect /nt60 H:
At this point the flash drive is bootable. Depending on what you plan on using the flash drive for you may want to copy some additional files to it. For instance you could copy the Windows installation DVD to your flash drive. Likewise, you may want to use the flash drive to run various diagnostic utilities. Regardless of how you plan to use the flash drive however, your computer will only be able to boot from it if the system’s BIOS is configured to allow USB booting.
So what do you do if your computer doesn’t support USB booting? I ran into this situation a while back with a netbook. It came with Windows XP, but I wanted to run Windows 7. Since the netbook didn’t have a DVD drive I opened the case and removed the hard drive.
I transplanted the hard drive into a full blown laptop that did have a DVD drive, inserted my Windows 7 DVD, and then booted the laptop and began the installation process.
One thing that you need to know about this technique is that Windows is hardware specific. You can’t normally install Windows and then transplant the hard drive into another system and expect it to work (although I once got lucky trying that). The trick to making this technique work is to cut the power when the computer reboots for the first time during setup. Up to that point the only thing that has happened is that Setup has copied all of the Windows 7 files to the hard drive and it has made a change to the hard drive’s boot sector instructing it to continue the setup process after the reboot. This is important because at this point the hard drive has everything that it needs for installing Windows, but nothing hardware specific has been written to the drive at this point.
Needless to say, I simply cut the power at the first reboot, put the hard drive back into my netbook, and then powered it up. Windows Setup loaded and proceeded to install Windows 7 onto the netbook.
Brien Posey is a 20-time Microsoft MVP with decades of IT experience. As a freelance writer, Posey has written thousands of articles and contributed to several dozen books on a wide variety of IT topics. Prior to going freelance, Posey was a CIO for a national chain of hospitals and health care facilities. He has also served as a network administrator for some of the country's largest insurance companies and for the Department of Defense at Fort Knox. In addition to his continued work in IT, Posey has spent the last several years actively training as a commercial scientist-astronaut candidate in preparation to fly on a mission to study polar mesospheric clouds from space. You can follow his spaceflight training on his Web site.