ERROR

[Ammasuddet]

Hi i am a student at Royal institute of technology.

I am using Virtualbox and a linux program called New tiny debian. For programming C in emacs.

I have a Macbook pro retina and i have used virtualbox without any problems untill today.

This is the Error message i get

Failed to open a session in the virtual machine NewTinyDebian.

VT-x is being used by another hypervisor.
(VERR_VMX_IN_VMX_ROOT_MODE).

VirtualBox can't operate in VMX root mode. Please close all other virtualization programs.
(VERR_VMX_IN_VMX_ROOT_MODE).

Details:
Resultscode: NS_ERROR_FAILURE (0x80004005)
Component: Console
Interface: IConsole {1968b7d3-e3bf-4ceb-99e0-cb7c913317bb}

What shall i do?

Allready deleted the program and files connected to virtualbox and newtinydebian.

Reinstall doesn't work.

// John

[mpack]

Cross posting is not allowed, so I have deleted your other message.

Why did you reinstall? The message indicates that another application is already using VT-x - if correct then reinstalling VirtualBox will not change that.

There seems to be some discussion about whether v4.2.0 has a bug in this area on Mac hosts, in the meantime I suggest you stick with v4.1.22 or v4.1.20, and check for another running hypervisor or debugger which could be using VT-x.

[mpack]

Actually, it looks like the problem is some kind of interaction with a Mac OS X host update, so downgrading VBox may not help. Read this bugtracker ticket, note the hotfix download.

[michaln]

Actually, it looks like the problem is some kind of interaction with a Mac OS X host update, so downgrading VBox may not help.

It definitely won't. Which should be obvious since it wasn't a VirtualBox update that broke things. Downgrading OS X would have helped, but shouldn't be necessary.

Read this bugtracker ticker, note the hotfix download.

Indeed.

[mpack]

Which should be obvious since it wasn't a VirtualBox update that broke things

There is nothing obvious about it. I consider myself quite good at debugging, having learned not to make assumptions. A MAC OS X update exposed a problem, which is not proof that the update was at fault. I have no first hand knowledge of which side has any bug, I simply reported the facts known to me - and chose my words quite carefully in that regard.

[michaln]

There is nothing obvious about it. I consider myself quite good at debugging, having learned not to make assumptions. A MAC OS X update exposed a problem, which is not proof that the update was at fault.

Sure - but it strongly hints that downgrading VirtualBox is probably not going to make any difference. Basically if A.2 + B.1 works, A.2 + B.2 doesn't, chances are A.1 + B.2 won't work either. The question here isn't what's at fault, just which pieces work together and which don't

In this particular case, OS X 10.8.2 on the 2012 Macs really won't work with any VirtualBox version released before today. Which admittedly is something we could have only guessed at a day or two ago, and yes, assumptions are dangerous.

[mpack]

Sure - but it strongly hints that downgrading VirtualBox is probably not going to make any difference.

Which is what I said - and without adding the extra bits that I have seen no evidence for.