Installing Windows 8.1 64 preview in VirtualBox

In order to install and use Windows 8.1 preview/Windows Server 2012 R2 preview in VirtualBox, you have to run this command:

"c:\Program Files\Oracle\VirtualBox\VBoxManage.exe" setextradata "VM Name" VBoxInternal/CPUM/CMPXCHG16B 1

You can see your VM names using this command:

"c:\Program Files\Oracle\VirtualBox\VBoxManage.exe"  list vms

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