This happens after updating into the MacOS Bug sur. And then trying to start the VirtualBox VMs, Tried so far and no luck with below options,

  1. Un-installed and re-installed the VirtualBox
  2. Created completely new VM and tried
  3. Re-installed Oracle_VM_VirtualBox_Extension_Pack-6.1.16

Anyone else came a cross with the same issue? any clue to resolve this would really appreciated.

This the the complete Error message

Failed to open a session for the virtual machine New Ubuntu.

The virtual machine 'New Ubuntu' has terminated unexpectedly during startup with exit code 1 (0x1).

Result Code: NS_ERROR_FAILURE (0x80004005)
Component: MachineWrap


  • 1
    Running brew install virtualbox from the terminal did the job for me, and “allow oracle” in “Security & Privacy” Jul 15, 2021 at 20:30
  • 1
    brew install virtualbox corrected the issue for me as well.
    – StevieD
    Jan 21 at 16:56

3 Answers 3


This worked for me

sudo su
csrutil clear
  • Then uninstall (from the official uninstaller) and re-install VirtualBox
  • If prompted, go to System Preferences - Privacy - General and accept the extensions
  • Reboot
  • I had to do this again after updating Big Sur to 11.5. But I did not have to uninstall VirtualBox though. Thanks for this guide.
    – ond1
    Jul 23, 2021 at 8:53
  • This also worked for me but instead of becoming root I just used: sudo csrutil clear and then rebooted the machine + the reinstalling vbox
    – joonasj
    Aug 16, 2021 at 8:54
  • Hit me out of the blue after doing the 11.5.2 update. Thanks for the guide. (I also note that their installer now specifically says you have to reboot after install on Big Sur.)
    – heavyboots
    Aug 27, 2021 at 17:42
  • 3
    This did not help me, unfortunately.
    – Dronir
    Sep 8, 2021 at 10:11
  • 1
    I'll add to my previous comment that I was dumb, and forgot I was on my M1 mac, where VirtualBox should not even work at all.
    – Dronir
    Sep 23, 2021 at 6:31

I was reluctant to install using Homebrew rather than an official package, but it did resolve the problem for me. This command:

brew install --cask virtualbox

Installed a later version of Virtualbox (7.0.6) than any available on the Virtualbox website (6.1.40), and the new version worked on Mac OSX Ventura, while 6.1.40 did not (even after reinstalling and Allowing the kernel extension).

See also: https://stackoverflow.com/questions/13670176/virtualbox-error-kernel-driver-not-installedrc-1908#comment119766775_56758118 and https://www.virtualbox.org/ticket/19795.


I received an error like this when trying to open a VM from the VirtualBox UI. (This was my first time installing VirtualBox or any VM.) I was able to run the VM from the commandline using:

VirtualBoxVM --startvm <VM ID or unique name>

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