The Error is caused because of a problem with a system file. there's nothing to do with it other than reinstalling the host operating system..
I disagree / disbelief that! Just run a test on a machine supporting VT-X. Disable VT-X support in Virtualbox and you will get a bluescreen with error 0xC0000260 (as discussed above). Enable the PAE/NX option, and you will get the error mentioned by
POS.
Then simply enable VT-X support in Virtualbox - both errors are gone (without reinstalling oder repairing the host os) - this is the result of several tests I run here in my environment.