i recently tried in installing windows 8.1 into my Debian Linux Jessie via Virtualbox. Installed virtualbox from debian repo and windows installment goes fine but with no luck booting the system. Error Code is 0x000000C4.
Solution: Problem caused by missing CMPXCHG16B instruction set. So we should manage it from console. Close your virtual machine
and give the command below;
$vboxmanage setextradata virtualmachinename VBoxInternal/CPUM/CMPXCHG16B 1