0xC0000225 Error trying to install Windows 2008 R2 or other x64 Windows under Virtualbox

This is just a quick tip to remind myself and in case anyone else stumbles upon the same problem.

While installing Windows 2008 r2, I encountered a 0xc0000225 error immediately after starting the boot from the iso. It turns out that you need to edit the settings for the VM to turn on IO APIC (Under System, Motherboard tab) in order for the install to complete. Soon as I did that, the install continued as normal.

Simple fix, hopefully it helps someone pulling their hair out in frustration.