Virtual Machine has Terminated unexpectedly during startup

[pinkfloydx33]

My virtual box installation is no longer working. Every time I try to run a machine I get the following error:

Failed to open a session for the virtual machine sfdgh.

The virtual machine 'sfdgh' has terminated unexpectedly during startup with exit code -1073741819 (0xc0000005). More details may be available in 'C:\Users\UserName\VirtualBox VMs\sfdgh\Logs\VBoxHardening.log'.

Result Code: E_FAIL (0x80004005)
Component: MachineWrap
Interface: IMachine {85cd948e-a71f-4289-281e-0ca7ad48cd89}

My machines were all working correctly up until recently. I'm not sure exactly when, but I suspect that it stopped working after installing the most recent windows updates.
I am currently on Windows 10 Professional, x64, Version 1803 (OS Build 17134.81) running Virtual Box 5.2.12r122591

None of hosts are working (all with the same error). I created a new machine to verify and that one does not work either. I have done the following:

• Verified Windows Feature Hyper-V is disabled
• Verified Windows Feature "Windows HyperVisor Platform" is disabled
• Verified nothing has changed in my BIOS; Running Securable.exe indicates that hardware virtualization is enabled
• Uninstalled Virtual Box [followed by reboot]
• Deleted .VirtualBox folder in User Profile
• Reinstalled (Right-click installed -> Run As Administrator) [followed by reboot]
• Tried enabling/disabling 3d Acceleration (suggested elsewhere)

I still receive the errors. I have attached my VBoxHardening Logs. Any ideas on what is causing this and/or how I can resolve it? Looking through the log I see mention of cyprotectdrv64.sys which I think might be Cylance (which is what our company has been using for antivirus). We've been having issues with that lately; it appears they've restricted some of our usage and as developers we've had to have them unblock a lot of things. Before I request that TechOps white-list VirtualBox I'd like to be sure that is what is going on.

[andyp73]

2e44.19a0: supR3HardenedWinFindAdversaries: 0x8000
2e44.19a0: \SystemRoot\System32\drivers\cyprotectdrv64.sys:
2e44.19a0:     FileDescription: Cylance Protect Driver

This is something that is known to not play nicely with VirtualBox as a Google search for "cylance site:forums.virtualbox.org" shows.

I think you need to talk to the TechOps and either have VirtualBox added as an exception or have it removed - even if only temporarily to prove whether it is the problem.

As you have moved to Windows 10 v1803 it would also be good if you took a quick look at whether DeviceGuard, CredentialGuard and the new containerised version of Edge are enabled in the Windows settings as these all make use of Hyper-V without telling you and may cause you problems down the road when you get over this hurdle.

-Andy

[socratis]

Point your TechOps to the FAQ Diagnosing VirtualBox Hardening Issues, it contains the in depth details about the what and the why you're seeing that error.