Dual boot Windows 8 and Windows 10 Technical Preview using VHDX
Want to try Windows 10 Technical Preview but don’t want to create a virtual machine or modify the current installation. Then create a virtual hard disk (VHD) dual boot system alongside another version of Windows (8 or 8.1).
Use virtual hard disk for the download Windows 10 TP next to another version of the operating system is more flexible than a virtual machine. In simple words this means that Windows 10 will be able to fully use the capabilities of the hardware of your computer.
In this guide you will learn how to use Deployment Image Servicing and Management (DISM) to install the image of the Technical Preview on a virtual hard disk and create a dual boot with previous versions of the operating system.
Important: this method is only supported on Windows 8 and later versions of the OS, and hard disks that don’t use BitLocker.
Download ISO image of Windows Technical Preview and extract all the files in one folder.
Open the tool «disk Management», click «Action» and select «Create virtual hard disk».
Use the VHDX file format and specify the size of your virtual hard disk (I chose 22 GB).
Select a location to store the new VHDX (it is preferable to select the «C: location»). In my example this is C:Windows10TPVirtualDrive. Then click «OK».
Now we need to initialize the new disk. To do this, click the right mouse button, click on «Initialize disk», select GPT and click OK.
Now click the right mouse button where it says «Unallocated» and select «new simple volume». In the new volume wizard, you can leave the default settings – just click «Next» and finally click «Finish».
Next, open the folder in which you extracted the files the ISO image of Windows Technical Preview and go to the directory «Sources». Copy the full path to this directory.
Now open a command prompt as administrator, type «cd», paste (paste) the copied path and press Enter. The following is an example command:
Now it’s time to run the DISM (Deployment Image Servicing and Management) to apply the install.wim to a new virtual hard disk.
In the command prompt window, type the following command and press Enter:
dism /apply-image /imagefile:install.wim /index:1 /ApplyDir:F:
where «F» is the drive letter you’ve assigned to the new virtual hard disk.
Once DISM completes its work, you need to make sure the new drive was recognized by the loader. To do this in the command prompt, type the following command and press Enter:
In this command, too, do not forget to replace the letter «F» with the letter of your drive.
Finally, restart the computer and at the boot menu, select Windows Technical Preview. Then you will need to complete the installation process.
During the configuration of Windows Technical Preview you will be prompted to enter a product key. Use the one that offers Microsoft: NKJFK-GPHP7-G8C3J-P6JXR-HQRJR.