Today I had problem on my Windows 8.1 laptop with VirtualBox, I wanted to create linux virtual machine in virtualbox and there were only 32bit systems on the list.
So I googled the problem and found blog post:http://www.fixedbyvonnie.com/2014/11/virtualbox-showing-32-bit-guest-versions-64-bit-host-os/
Summary from the post available in the link above:
- Your Host OS is 64-bits
- Intel Virtualization Technology and VT-d are both enabled in the BIOS
- The Hyper-V platform is disabled in your Windows Feature list.