VT-x is being used by another hypervisor

[MeesterP]

Hi all,

Since today my vm's won't start anymore, giving me an error: VT-x is being used by another hypervisor. (VERR_VMX_IN_VMX_ROOT_MODE).
I have no other virtualisation software running on my Windows 7 box.. (not hyper-v, not vmware or anyhting like it)

The last weeks it was working smoothly, and suddenly today, it won't start

here's the complete error message (excuses for some of the language.. it's Dutch):

Code: Select all

Het is niet gelukt een sessie te openen voor virtuele machine andy.

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).

Resultaatcode:E_FAIL (0x80004005)
Component:Console
Interface:IConsole {8ab7c520-2442-4b66-8d74-4ff1e195d2b6}

Can anybody hand some tips on what to do ?

Thanks
P.

[noteirak]

Well, what changed since last week? Any new software installed? Any change in the BIOS? Any configuration change to the system?

[scottgus1]

Once I installed a trial of BitDefender Antivirus, and I found it took VT-x away from Virtualbox. Uninstalling BitDefender allowed Virtualbox to use VT-x again.

So other programs besides hypervisors can use VT-x, and as noteirak says, look at whatever you may have changed since the guests ran successfully.

[MeesterP]

Since yesterday, nothing really changed, except the Windows Updates, so I suspect it has something to do with that,
but then again, there shoul be loads more people having issues

I do use bitdefender by the way, but there has not been an issue before today

Edit: I also have a Win7 laptop, also running Birdefender, and VirtualBox runs just fine in that environment.

[scottgus1]

Is the last time you ran your guests yesterday or last week? The original post seems to imply more time since the last successful run of the guests. More things may have changed than just Windows Updates.

One thing to try: See if you can turn off all other unnecessary bootup processes and see if VT-x comes back. Then turn the processes back on one at a time until VT-x gets used again. Also, Windows Updates will usually run a System Restore point to take the OS back before the updates were installed in case something went wrong. You could try to restore to that point and see if your VT-x comes back.

[MeesterP]

I used the system yesterday, and it was just fine.
When I shut down the pc for the night, windows installed 4 updates I believe.
I have been fiddling with Autorun Organizer to see if anything changes when I stop using some items... no difference so far


here's a list of installed updates yesterday at shutdown: (Again.. sorry for the Dutch language)

not allowed to post urls I'm afraid, go bit.ly(slash)1CiIqK5

[loukingjr]

See: viewtopic.php?f=6&t=64777#p304974

I noticed you have KB3004394 installed although it's been installed for awhile.

[MeesterP]

It says to install KB3024777, so I did just that..
The executable (KB3024777-amd64.exe) that gets downloaded does not do anything... no activity whatsoever (not as user, not as administrator). It doesn't show in the updates-history either..

Also, that KB3004394 has been instlled yesterday.. 11 february 2015

anyway, VirtualBox is still very much broken

[mpack]

VirtualBox is still very much broken

Not really. It if tells you that VT-x is already in use, then it's already in use. It is not wrong.

[loukingjr]

Also, that KB3004394 has been instlled yesterday.. 11 february 2015

So it was. Perhaps Microsoft issued an update recently.

edit:Apparently they have. I just checked in my guest

[loukingjr]

mpack is correct btw, something must be using VT-x

[MeesterP]

mpack is correct btw, something must be using VT-x

any clues about how I can pinpoint that ?
If it's BitDefender, then I will have to forget about virtualization.. BD is the best antivrus around ...

[loukingjr]

no idea. I only run Windows as guests. Someone else might of course.

[noteirak]

I don't know how you can find out what is using VT-x. I don't even know if that's possible in the first place. A quick google search doesn't give me any indication it is...
Did you check your BIOS to be sure it is still enabled?

[MeesterP]

Hi guys,

I managed to get things running again.
It was Bitdefender messing up after all.
After I did a repair of the Bitdefender installation (as per this instructions: www(dot)bitdefender(dot)com(slash)support(slash)how-to-repair-bitdefender-2015-1311(dot)h t m l) my vm (Andy) that uses VT-x started up once more.
Now I'm keeping my fingers crossed that it won't break again

Thanks all for contributing to this thread. Much appreciated

P.