If you get VERR_NEM_VM_CREATE_FAILED when starting a virtual machine in Oracle VirtualBox, reboot the host system and if that doesn't work, check out these solutions.

Open Oracle VM VirtualBox, go to the Devices menu, and click Upgrade Guest Additions. Upgradation will take some time, so wait for a few minutes. Now, check whether the Guest Additions upgraded.

Oracle VM VirtualBox is available in versions that run on Windows, Linux, or OS X. All these versions can create virtual machines based on any of dozens of different operating systems, including ...

Oracle's VM VirtualBox is a powerful, free, and open-source virtualization tool—but you'll have to do some tinkering to make it work for you.