What is vMotion
vMotion is a component of VMware vCenter which allows for the live migration of a VM system from one host to another while the virtual machine is running. This will result in no downtime for the VM or disruption for end users.
When making use of vMotion, certain aspects of the VM might change, which will cause your UI to lock you out because your serialization has become invalid. Should this occur, simply following this guide > Clearing your License