Hi Bossmaster
I just had the same problem, and I solved it by removing the VM from the inventory and then re-registering the VM on the same host, which solved the problem.
When the VM was shut down, it was put in an inaccessible mode. Once the VM is in this state, you need to go to the datastore where the VM is located and look for the .vmx file. Select it and the option to register the VM will become active. Select it and you will be presented with options to register the VM, which will depend on your needs and infrastructure.