Thursday, June 27, 2013

Installing Windows 8.1 in VirtualBox

When I tried to install the 64-bit version or even upgrading my already existing 8.0 install I kept getting Error 0x000000C4 until I found a fix on the Web.

I had to run the following at an administrator command prompt (all on one line):

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

Replace [vmname] with the name of the virtual machine you want to add the instruction to. If your vm name has spaces in it, enclose it in quotes.

This command adds the CMPXCHG16B CPU instruction that's missing from the default configuration of VirtualBox.

That's all it takes and then you can install Windows "Blue" 8.1 and give it a run.