Just to be clear about the setup: do you have an opennebula frontend as VM running inside of vmware workstation, and an opennebula worker as another VM inside of vmware workstation (or maybe the frontend and worker are the same VM)? Is nested virtualization enabled in vmware workstation for the worker VM https://blog.fpmurphy.com/2016/10/nesting-rhel7-kvm-on-vmware-workstation-12.html https://www.youtube.com/watch?v=FflA9j61LvE? Try to start a VM manually on the worker to see whether it boots Can not instant VM - in this way you can control the os-variant used. Look also at the discussion about VM template settings https://forum.opennebula.io/t/how-to-create-windows-vm/