It is the very first troubleshooting suggestion you should follow in order to get rid of this problem from your Windows computer. Third-party virtual machine apps, such as VirtualBox, VMware ...

Microsoft released a developer preview of Windows 8 last night and surprisingly made it available for general public too. Though this brand new OS is half-baked and is meant to be used by developers ...

It is the first thing you need to fix the issue as stated above. For that, you need to run the virtual machine showing the error and go to the Devices > Install Guest ...

If you find yourself with a mismatched VirtualBox and VirtualBox Extension Pack release, such that VirtualBox itself cannot resolve, Jack Wallen shows you how to fix this from the command line.