For other version of windows prior to window 8, we may get VirtualBox installed without any problem. But with windows 8( mine is 8.1 pro), after getting VirtualBox installed, the options for creating 64-bit machine don’t appear. All is 32-bit. After googling, I found that we also need to turn off the “hypervisorlaunchtype ” off as following:
1. Open command(terminal)
2. Type below command:
bcdedit /set hypervisorlaunchtype off
3. Restart to take effect.
Note that we need to Enable Virtualization feature on the CMos in order to get virtualbox worked