virtualbox.org

I spoke too soon...
Today, after a reboot, the same issue arrised again. So I repaired BitDefender gain, and was able to continue.
It seems that you have to go through this cumbersome route to get it to work each and every day

I'm afraid that we are not in a position to tell what what software is running on your PC. It clearly isn't a VirtualBox problem, so I find it rather irritating that you marked this thread as "not solved". If you have a problem with BitDefender then go get support from them!

As I said above: if VirtualBox tells you that VT-x is in use, then VT-x is in use. Stop thinking it's a mistake, or a bug, or a lie, just go fix it.

if I mark this issue as "solved" it could be misleading for other people with the same issue. They will expect to find a solution. Repairing bitdefender seems only a workaround and not a solution.
maybe, there will come along a bright mind with a great idea.

I can change the title to work-around if that's a better option

MeesterP wrote:if I mark this issue as "solved" it could be misleading for other people with the same issue. They will expect to find a solution. Repairing bitdefender seems only a workaround and not a solution.
maybe, there will come along a bright mind with a great idea.

I can change the title to work-around if that's a better option

How about not marking it at all?

loukingjr wrote: How about not marking it at all?

Also an option

Sorry if I am posting on an old thread, but I need help.

I am using a laptop "Lenovo ideapad Z510" with Microsoft Windows 10 Professional as host and GNU/Linux Mint 17.3 MATE 64 bit edition as guest and VirtualBox 5.0.10 r104061, I have installed Bitdefender Antivirus PLUS 2015 since 10 months and I have already turned off Hyper-V feature, I have just controlled and Hyper-V is still turned OFF.

Two days ago, december, 19th, 2015 VirtualBox has run smooth and round. NO issue at all. Great.

But right now I am unable to run my guest and I get this message (it is partly in Italian because installed VirtualBox is in Italian language):
"
Apertura di una sessione per la Macchina Virtuale mint17.3Ext non riuscita.

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).

Codice 'uscita: E_FAIL (0x80004005)
Componente: ConsoleWrap
Interfaccia: IConsole {872da645-4a9b-1727-bee2-5585105b9eed}
"

I have not changed any configuration, I have not installed any new software, but I have checked and yesterday, december, 20th, 2015, Microsoft has pushed and installed this Microsoft Update "Update for Microsoft Windows (KB3124200)", Bitdefender has usually installed updates to signature files but no Bitdefender updates that has requested a restart.

I am really desperate and I am in need of help, also because if it is not Hyper-V who is the "other" hypervisor, who is it?

I need VirtualBox principally for his portability and I can not migrate to another kind of hypervisor. I need to use VirtualBox with this laptop because it is my job computer.

Thank in advance to anyone who has read until here and best regards,

Andrea Boccaccio

The first thing to try is uninstalling "Update for Microsoft Windows (KB3124200)" and see if everything is back to normal.

loukingjr wrote:The first thing to try is uninstalling "Update for Microsoft Windows (KB3124200)" and see if everything is back to normal.

Done, and it is back to normal so the issue is that Update.

Unfortunately this lead to an unsolvable situation because "Update for Microsoft Windows (KB3124200)" is mandatory, because IMHO it is a security update. I mean I have turned on "Defer Updates" but this setting is unable to defer security updates, in Microsoft Windows 10, security updates are mandatory, meanwhile I am writing this post, the Update is automatically downloading and above all I am unable to defer it.

How may I cope with this issue? What to do? It is clear that I can not uninstall everytime this update.

Thanks for the help and for any advice past and future,

Andrea Boccaccio

See this: https://support.microsoft.com/en-us/kb/3073930

Thanks a lot it worked , I have hidden "Update for Microsoft Windows (KB3124200)" and it seems that WIndows have not tried again to reinstall it.

Anyway it makes me wonder, is it a bug? Or that update is installing an hidden hypervisor? Or what else?

Finally I think that hiding a system security patch is not a solution that leads to my complete satisfaction, I mean if that security update fixes also a security breach, I am not at my ease to cope with an issue simply avoiding its installation.

Anyway thanks again, best regards,

Andrea Boccaccio

You're welcome.

Unfortunately Microsoft has been releasing broken updates not just for Windows 10 but their other versions as well. Eventually they come out with a new update to fix the old update.

I'm not sure why it broke your install. It's just that when someone has a perfectly good install and something updates and something breaks, there is a very good chance it's the update.

FWIW, lately Windows 10 updates have also been removing already installed programs they think won't work with Windows 10 so it's hard to diagnose.

I encountered this same issue after upgrading from Win7 to Win10. BitDefender (v2016) was acting a little "quirky" as well. Following the "repair" procedure detailed by Meesterp, (using Windows 'Uninstall or change a program' from Control Panel), and the requisite reboot resulted in correcting the problem of VirtualBox reporting that VT-x was in use by another hypervisor.