Microsoft released a preview of the upcoming service pack to Windows 8, named Windows 8.1 and also codenamed Windows Blue. As a user of Windows 8, I wanted to see what are the changes that could be expected when the update becomes live and therefore decided to fire up and test the new OS inside VirtualBox.
I downloaded the 64-bit ISO from this webpage. The page also gave away a preview product key to be used.
Then, I created a new virtual machine inside VirtualBox using the default WIndows 8 configuration. I then turned on both 3D and 2D acceleration support, and mounted the Windows 8.1 ISO to the virtual machine. However, the virtual machine failed to boot with 0x000000C4 error.
![0x000000C4 Error](https://blog.hazrulnizam.com/wp-content/uploads/2013/07/WindowsBlueInstall01-300x244.png)
Luckily, someone else had already come across this problem, and created a VirtualBox support ticket. The solution can be found here, which requires an extra setting to be configured on the virtual machine.
"C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" setextradata [VM_name] VBoxInternal/CPUM/CMPXCHG16B 1
VM_name should be set to the name you have given to the virtual machine. This can be double-checked using the following command:
"C:\Program Files\Oracle\VirtualBox\VBoxManage.exe" list vms
Now the ISO booted fine, and the installation can begin.
![Windows install start screen](https://blog.hazrulnizam.com/wp-content/uploads/2013/07/WindowsBlueInstall03-300x244.png)