How to Run a Portable Version of Windows XP, 7, 8, 8.1 from a USB Drive

Windows USBYou ever wanted a Windows to run on a USB hard drive or flash drive, to use on any computer you want? It’s possible :-D. Thanks to WinToUSB.
Here’s how to install a portable version of Windows 8.1 (or other versions, like Windows XP or 7) on a USB hard drive that you can take anywhere.
Note that this is different from installing Windows from a USB drive, which allows you to install Windows on a computer that doesn’t have a CD drive (for that, please check this post). Here, we’re actually installing Windows on a USB drive so we can run it from a drive on any computer you want, and take it with you for troubleshooting, remote work, and so on.

You only need:
  1. A Microsoft Windows installation disc or ISO image – We recommend using Windows 8, that will allow you to use your portable installation on any computer. Microsoft Windows 7 is not as portable and may have driver or activation issues if you use it on other computers.
  2. A USB drive – An external hard drive or a flash drive. USB 2.0 is not recomended (slower). A USB 3.0 driveis the best technology for this end (mutch faster).
  3. WinToUSB – This is the simple program that will walk you through the installation process. Download it from here.

This is a very easy to do… Only choose the ISO sourse, the destination disk, and configure the system partitions.

Check it on WinToUse:

On my PC it only takes less than 20 minutes, but I’ve read that some users wait an hour to do it.

You will need to make 2 partitions (system partition with +-300MB and a boot partition with the space that you desire – more than 30GB is recomended for Windows 8). You can check this page: for more information.



Create an OS instalation from an USB pen drive

This tutorial was tested with Microsoft Windows 7 Home Premium.

I’ve created a bootable installation of Windows 7 from an USB pen drive.

The steps you should follow to do that:


Step 1:

Windows Key + “R” key;



Step 2:


  • On the prompt of Disk Part type “list disk” to see the disks of your computer.
    • My USB pen drive is the disk 2.
  • Type: select disk “number of your usb disk” (CAUTION: Make sure that you know which is your USB disk drive).
  • “clean”
  • “create partition primary”
  • “format fs=fat32 quick”
  • “active”
  • “exit”

Step 3:

After configure this you can copy all the files of your Windows DVD (or other Operating System supported by this file system – fat32) to this USB drive. It is able to boot from this drive 😉